Quick answer. To compare repeated motions fairly, reduce each time to a clearly defined common denominator. With unequal cycle counts, a mean of trial periods and a pooled time per cycle answer different questions. Name the quantity, then select the operation.
In this guide. Worked ten-cycle and mixed-cycle examples, weighted means, rates, ratios, percentage changes, descriptive spread, graph gradients, interval decisions, rounding and SEC-style problem solving.
Why a clean number can answer the wrong question
Consider two stopwatch readings: 14.2 seconds and 10.1 seconds. The first is larger. Does that mean the first pendulum has the longer period? Only if the readings cover the same number of complete cycles, or if we first convert both into a common rate. Mathematics starts by asking what the numbers measure. The arithmetic comes second.
In the previous Physics guide, a 0.25 m pendulum had ten-cycle times of 10.1, 10.0 and 10.2 seconds. A 0.50 m example had 14.2, 14.1 and 14.3 seconds. This chapter uses that fictional classroom dataset to develop a different skill: comparing measurements fairly when totals, counts, rounding rules and assumptions may not match. We will compute means, distinguish unweighted from weighted averages, check ratios, test bounds and explain conclusions in words.
Your first useful rule is to draw three columns: elapsed time, number of cycles and time per cycle. Never compare the first column as though it were the third. This small discipline transfers to unit prices, speed, productivity, rates of reaction and every examination question where the denominator determines meaning.
What the 2027 G3 Mathematics syllabus actually assesses
The 2027 SEC G3 Mathematics subject code is K310, while 4052 is the earlier reference code. The official syllabus gives Paper 1 and Paper 2 two hours fifteen minutes each, 90 marks each and 50% weight each. Paper 1 contains approximately 26 short-answer questions, and Paper 2 contains nine to ten questions of varying lengths, with the last question focusing on a real-world mathematical scenario. Essential working matters. The syllabus normally specifies three significant figures for non-exact numerical answers unless the question says otherwise, with separate guidance for angles.
The pendulum figures here are original Mathematics practice, not a released SEC question. Students are expected to interpret data and graphs in context, justify reasoning and apply suitable techniques. A practical-looking story should not be mistaken for a claim that a particular Physics apparatus is assessed in Mathematics. The relevant skill is controlling quantities, units, ratios and inferences.
Read the official K310 syllabus and the 2027 G3 syllabus list for the authoritative scheme. Our calculations illustrate the mathematical processes described there without pretending to be official specimen material.
Define the unit of comparison
A ten-cycle total is measured in seconds per ten cycles. A period is measured in seconds per cycle. To convert, divide the total number of seconds by the corresponding count. For the shorter example 10.1 seconds over ten cycles yields 1.01 seconds per cycle. For the longer example 14.2 seconds over ten cycles yields 1.42 seconds per cycle. Only then is it meaningful to say that the second average period is larger by 0.41 seconds.
Units are not decorations added after working. They tell us which operation is legal. Subtracting two totals measured over unequal counts does not compare individual periods. Multiplying a period by a cycle count does produce an estimated total elapsed time, provided the period refers to the same repeating process and the model assumes that period is sufficiently stable over the interval.
An examination answer can communicate this reasoning in one line: period = total time divided by number of complete cycles. Then substitute the figures and include the final unit. A student who skips the explanatory line may still reach the number, but the line protects against using an attractive yet irrelevant denominator.
Average a set of equal-count trials correctly
The shorter pendulum’s three ten-cycle observations are 10.1, 10.0 and 10.2 seconds. Their sum is 30.3 seconds. Their mean ten-cycle time is 30.3/3 = 10.1 seconds, and their mean period is 10.1/10 = 1.01 seconds. Equivalently, 30.3 seconds covers thirty observed cycles across the three trials, giving 30.3/30 = 1.01 seconds per cycle.
For the longer pendulum, add 14.2, 14.1 and 14.3 to obtain 42.6 seconds over thirty cycles. The mean period is 42.6/30 = 1.42 seconds. The two approaches agree because all trial counts are equal. This equality makes the problem straightforward; later we remove the equal-count assumption.
Keep the original figures visible in your working. If you record only ‘mean 1.42’, a reader cannot tell whether it represents seconds per cycle, total seconds over multiple trials or a rounded derived estimate. State the measured object and the denominator. That is mathematical communication, not extra decoration.
Why unequal cycle counts change the arithmetic
Suppose a student has three valid trials for another setup: eight cycles take 11.6 s, ten cycles take 14.4 s, and twelve cycles take 17.4 s. Their individual period estimates are 1.45 s, 1.44 s and 1.45 s. The straightforward average of these three estimates is approximately 1.447 s. But if the purpose is to pool all observed cycles under an assumption of a stable period, add the elapsed times and divide by the sum of counts: (11.6 + 14.4 + 17.4)/(8 + 10 + 12) = 43.4/30 = 1.4467 s per cycle.
These values happen to be similar here. They need not be identical when trial periods differ more. The pooled answer weights each trial by its number of observed cycles. The unweighted mean gives each trial one equal vote. Neither convention should be chosen automatically without reading what the question asks.
If the question says ‘mean of the three trial periods’, calculate the unweighted mean. If it asks for ‘total time divided by total complete oscillations’, use the pooled measure. The mathematics is controlled by the meaning of the average.
A counterexample that exposes a weighted-mean mistake
Try an extreme educational example. One trial observes two cycles in 2 seconds, a period of 1.0 s. A second trial observes eighteen cycles in 27 seconds, a period of 1.5 s. The ordinary average of the two trial-period estimates is (1.0 + 1.5)/2 = 1.25 s. The pooled time per observed cycle is (2 + 27)/(2 + 18) = 29/20 = 1.45 s.
The numbers are not contradictory: each answers a different question. The first treats the two trial estimates equally; the second gives eighteen observed cycles nine times the weight of two cycles. It is easy to produce a false ‘mean’ by adding trial times and dividing by the number of trials when each trial contains a different number of cycles. Then the answer remains a mean trial duration, not a mean period.
Always identify what is being averaged. A single word such as ‘average’ does not tell us whether the unit is seconds per trial, seconds per cycle or frequency in hertz. Write the complete quantity in the final line.
Use a table with separate raw and calculated columns
Build a table with headings: trial, length (m), complete cycles, total time (s), estimated period (s per cycle). In the first row, ‘A1, 0.25, 10, 10.1, 1.01’ is meaningful only because the headings supply the units. In a second row, ‘A2, 0.25, 10, 10.0, 1.00’ allows the calculation to be checked. Do not silently replace 10.1 by 1.01 in the time column.
A table also makes unequal counts visible. If the three trials contain 8, 10 and 12 cycles, a quick glance prevents an incorrect comparison of the raw total times. It encourages correct weighted calculations and helps a student see whether the observations are comparable.
When copying data under time pressure, keep a short verification routine. Check the quantity, check the unit, check the denominator, check the row and then calculate. One incorrect copied value can spread into the mean, the percentage change, the graph and the final explanation. Rechecking the input is often faster than reworking an entire question.
Calculate an absolute difference and a relative difference
The means 1.42 s and 1.01 s differ by 0.41 s. This is the absolute difference in seconds per cycle. For a relative comparison based on the shorter value, calculate (1.42 − 1.01)/1.01 × 100%, approximately 40.6%. Thus the longer setup’s mean period was about 40.6% greater than the shorter setup’s mean period in the fictional data, using the shorter period as the reference.
But if you reverse the reference, the percentage is (1.42 − 1.01)/1.42 × 100%, approximately 28.9%. The absolute difference has not changed. The percentage has changed because its denominator changed. A sentence saying merely ‘a 40.6% difference’ hides which reference was used.
This is particularly important when a problem asks for ‘percentage increase from A to B’ rather than ‘percentage decrease from B to A’. Label the start value and the end value. Students who already understand fractions from Primary Mathematics can build powerful secondary reasoning by attaching meaning to the whole being compared.
Ratio statements require a named numerator
The ratio of the longer mean period to the shorter mean period is 1.42/1.01 ≈ 1.406. A reader may say that the longer period was approximately 1.41 times the shorter period. In the reverse direction, 1.01/1.42 ≈ 0.711. These are reciprocal comparisons, not competing answers to the same question.
Do not turn a measured ratio into a general physical law. The two lengths were 0.50 m and 0.25 m, a 2:1 length ratio. The period ratio is approximately 1.406:1. It is false to conclude that doubling length must always double period. Indeed, the fictional numbers do not show that. Nor do two points establish a relationship valid for every possible length.
The right skill here is interpreting proportional language. ‘Twice as long’ may describe the string length while ‘about 1.41 times’ describes the measured period. The same word ‘long’ can refer to a length or a time; a strong mathematical sentence specifies which one it means.
A second dataset tests the ratio carefully
Imagine a new classroom setting with two hypothetical measured periods: 0.90 s at one length and 1.20 s at another. The difference is 0.30 s and the ratio of later to earlier is 4/3. The percentage increase, using 0.90 s as the base, is 0.30/0.90 × 100% = 33⅓%. None of these results identifies the precise lengths, because none were supplied.
An exam question may ask whether a proposed statement is justified: ‘The string was one third longer.’ That statement does not follow from periods alone. A number about time does not determine a number about length unless a valid length–period model is provided or measured. The correct response states the missing relationship.
This distinction is useful well beyond pendulums. It is the same reason a bigger test score does not automatically prove more study time, and a larger total bill does not tell us that the unit price increased. Different quantities can move together without being interchangeable.
Round only when the question and precision permit
A pooled period of 43.4/30 seconds is 1.446666… seconds. If the task requests three significant figures, write 1.45 s. If the task specifically asks for two decimal places, again write 1.45 s. But keep the unrounded value in subsequent calculations when possible. Rounding to 1.4 s too early can affect the result of a ratio, percentage or difference.
The official K310 syllabus has a general instruction for non-exact numerical answers: three significant figures unless a different accuracy is specified, with angles treated separately. It is not a rule to round every intermediate expression to three digits. The best practice is to keep enough accuracy in working and round the reported answer at the end.
Also distinguish significant figures from decimal places. The value 0.00750 has three significant figures, even though it shows five decimal places. A stopwatch reading may constrain the sensible precision of a result, but the mathematical examination question’s explicit instruction remains important.
Understand that a precise display is not a guarantee
A calculator can show 1.4466666667 even when the recorded time was only to a tenth of a second. Those extra digits arise from division, not from a more precise stopwatch. If a practical measurement underpins the number, explain the limitation when interpretation is requested. If a pure Mathematics question supplies exact figures for a model, use the stated mathematical precision rules. Know which kind of task you are answering.
For example, suppose a question defines ideal times exactly to 0.1 s and asks for a model calculation. Your arithmetic can be exact within the model. An empirical report about a real observer has additional questions about reaction time and counting accuracy. The same decimal can have different evidential strength.
Do not use ‘approximately’ for everything, and do not use ‘exactly’ simply because the calculator produced a complete number. Match the expression to the source: given value, recorded observation, model assumption or rounded result. Readers need to know which one they are seeing.
Build a transparent range from repeated trials
For the length-B small-angle ten-cycle times 14.2, 14.1 and 14.3 seconds, the largest minus smallest is 0.2 seconds. Their individual period estimates are 1.42, 1.41 and 1.43 seconds, with a range of 0.02 seconds. Because every trial had ten cycles, the range is divided by ten as well. This is a descriptive measure of the spread of those readings.
Do not call the range a confidence interval. A range merely identifies the smallest and largest values observed in a sample. It does not say that all possible future readings will lie there or attach a probability to the unknown true value. More trials may produce a wider observed range.
Students often interpret a narrow range as proof of correctness. Repeated readings might be consistently biased. In Mathematics, range quantifies spread. In Science, judging accuracy requires additional information about the measurement process. These perspectives complement each other but are not interchangeable.
Analyse an added unusual reading
Add a fourth ten-cycle reading of 16.6 seconds to the length-B small-angle trial list. The original sum of 42.6 seconds becomes 59.2 seconds. The arithmetic mean of four ten-cycle times is 14.8 seconds, so the pooled period over forty observed cycles is 1.48 seconds. Sorted readings are 14.1, 14.2, 14.3, 16.6, giving median 14.25 seconds for ten cycles, or 1.425 seconds per cycle.
The mean changes more than the median because the high reading pulls it upward. The Mathematics conclusion is that these two summary measures respond differently to an extreme value. The Science question, whether the high reading came from a valid run, needs further evidence. We cannot delete it just because it is inconvenient.
An examiner may ask which measure is more representative in the described context. Give the actual reason: if a visibly anomalous reading is present and no further information is available, the median can communicate the centre with less sensitivity to that high value. But report that choice explicitly.
Do not silently mix seconds and milliseconds
Suppose another instrument reports a ten-cycle time as 14,250 milliseconds. Since 1,000 milliseconds equals one second, that is 14.25 seconds, giving mean period 1.425 seconds. A hurried student may copy 14,250 into a column labelled seconds and report a period of 1,425 seconds. The arithmetic is consistent with the mistaken units, making the final error enormous.
Write conversions before substitution. 14,250 ms ÷ 1,000 = 14.25 s, then 14.25 s ÷ 10 cycles = 1.425 s per cycle. The order keeps the quantity visible. If the question asks for the period in milliseconds, you may instead divide the original 14,250 ms by ten to obtain 1,425 ms per cycle.
The result is the same physical duration in two units. This is a simple yet important example of dimensional reasoning. Strong students understand that a large number does not necessarily represent a large time; it may be an ordinary interval expressed in smaller units.
Interval estimates from stated measurement bounds
Imagine the task explicitly states that a ten-cycle total reported as 14.2 seconds lies between 14.15 seconds and 14.25 seconds. For exactly ten observed cycles, dividing each endpoint by ten gives a mean-period interval from 1.415 s to 1.425 s. These are bounds derived from the supplied interval; they do not measure the observer’s reaction-time error unless the question says the interval includes it.
We can compare this with another interval, say 1.005 s to 1.015 s for the shorter setup. The intervals do not overlap, so the longer one remains greater throughout the stated bounds. That strengthens the comparison within the specified assumptions. It does not prove a universal relationship between every possible length and every future period.
A different question may define rounding to the nearest tenth, in which case careful use of strict and non-strict endpoints matters. Always read whether the interval is inclusive, exclusive or inferred from rounding convention. Bounds are logical consequences of stated conditions, not labels one can attach freely.
The denominator must reflect the counted cycles
Suppose the record says, ‘The stopwatch ran for 13.8 s, but the student counted only nine complete cycles before stopping.’ If those nine cycles are valid observations, the estimated period is 13.8/9 ≈ 1.53 s. Dividing by ten because the original plan intended ten cycles would be a denominator error. The denominator must describe what actually happened, not what the student hoped would happen.
However, if the cycle count is uncertain, no precise period can be justified. Writing ‘perhaps nine or ten’ requires either a bounded interpretation or repeating the measurement. If it was nine cycles, the calculated period is about 1.53 s; if ten, 1.38 s. That is a substantial range caused entirely by uncertainty about count.
The lesson generalises to surveys with missing responses and rates with changing exposure. A denominator is not a minor number below a fraction bar. It defines the population or quantity to which the result applies.
Design a graph before choosing its interpretation
Plot mean period on the vertical axis against effective pendulum length on the horizontal axis if the task asks how period changes with length. Use metres and seconds in headings. With only the points (0.25, 1.01) and (0.50, 1.42), we can say the second observed point is higher. We cannot conclude that the relationship is a straight line or deduce a universal gradient from only those observations.
If the task supplies several lengths, calculate each mean period first. Place points carefully and consider whether a curve or straight line is supported. Never draw a line through the origin solely because it looks attractive. A line may be a visual model; it is not an observed fact beyond measured values.
A Mathematics paper may ask you to interpolate or extrapolate using a model explicitly supplied by the question. In that case distinguish the model prediction from a measured reading. Show the calculation and state any requested assumption. Graphs communicate patterns, not a licence to invent an unsupported physical theory.
Difference between a graph gradient and a period
Suppose a graph plots total elapsed time against number of complete cycles for a stable ideal setup. Points such as (0,0), (5,7.1), (10,14.2) and (15,21.3) lie on a straight line, with time in seconds on the vertical axis and cycle count on the horizontal axis. The gradient is change in time divided by change in cycles, 14.2/10 = 1.42 seconds per cycle. In this particular model, the slope represents the average period.
If the graph instead plots number of cycles vertically against elapsed seconds horizontally, the gradient is cycles per second, or frequency. It would be about 0.704 Hz for the same ideal motion. Swapping axes changes the meaning of the gradient even if the underlying observations do not change.
This is why ‘find the gradient’ is not a complete interpretation. Name the axes, compute the rise over run and attach the compound unit. An examiner can reward accurate method even when the context is unfamiliar.
A two-stage calculation with a known period
A fictional display device completes forty cycles with constant ideal period 1.25 seconds. Its total time is 40 × 1.25 = 50 seconds. A second setup with period 1.40 seconds would take 56 seconds for forty cycles, a difference of 6 seconds. If the question instead asks how many complete cycles fit into fifty seconds at 1.40 seconds per cycle, 50/1.40 ≈ 35.7; only thirty-five complete cycles would fit if the cycle count must be a whole number and any partial cycle cannot be counted.
Do not round the number of complete cycles to thirty-six without checking the wording: thirty-six cycles would require 50.4 seconds and exceed the available time. Rounding to the nearest integer is not always the appropriate decision rule. Context determines whether you take a floor, ceiling or nearest estimate.
This ability is central in real-world mathematics. A calculation can produce a decimal, but a plan that counts whole objects, complete events or full sessions must interpret the result before reporting it.
Test a proposed headline numerically
A proposed classroom headline says, ‘Doubling the string length doubles the measured period.’ The lengths in our packet are 0.25 m and 0.50 m, so the length did double. The measured periods were 1.01 s and 1.42 s. The ratio of measured periods is approximately 1.41, not 2. Thus the headline is not supported by the two supplied readings.
Another headline says, ‘The longer setup was 41% slower.’ The word slower may be ambiguous: are we describing cycles per second, movement speed along an arc or a time per cycle? We can responsibly state that its average period was about 40.6% greater with the shorter period as the reference. This is clearer and avoids the unmeasured concept of arc speed.
Numbers do not speak for themselves. They require a named quantity and reference. That is why good Mathematics answers include a short final sentence that interprets the operation, rather than stopping at the calculator result.
A correction exercise with unequal numbers of trials
A student has two trials: ten cycles in 14.0 seconds and twenty cycles in 29.0 seconds. They write, ‘The average period is (14.0 + 29.0)/2 = 21.5 seconds.’ The line has averaged total trial durations, not periods. The correct individual periods are 1.40 and 1.45 seconds. If the question asks for their unweighted mean, it is 1.425 seconds. If it asks for the pooled period over thirty cycles, it is 43.0/30 ≈ 1.433 seconds.
Both derived answers are defensible when tied to the appropriate wording. The student’s number 21.5 seconds is a valid average of the raw trial durations, but it does not answer the period question. Recognising that difference is more powerful than memorising a single formula.
A helpful study habit is to explain your answer as though another student must decide whether the denominator is trials or cycles. If you can justify the denominator in plain English, you probably understand the mathematical operation.
A correction exercise about inconsistent precision
A student reports an original ten-cycle time of 14.2 s and a calculated period of 1.420000000 s. The arithmetic is not wrong, but the format can imply far more measurement precision than the stopwatch record supports. If the question has a stated rounding rule, follow it; if the task asks for scientific evaluation, discuss the actual resolution and timing uncertainty.
A second student rounds 1.425 to 1.4 before calculating a percentage difference. Their final percentage may change needlessly. Keep the full working value until the final answer. A third student writes ‘1.42 hz’ as the period; the number and unit describe different quantities. Use s for period and Hz for frequency.
These three errors have different remedies: display precision, intermediate-rounding discipline and conceptual unit correction. An error log that calls all of them ‘carelessness’ gives no useful direction for improvement. Name the precise failure.
Bound a decision instead of pretending to know the exact value
Suppose a hypothetical teaching task states that a timing system will pass a check if the mean period is less than 1.43 seconds. One estimate is 1.425 s with an uncertainty interval from 1.415 to 1.435 s under the stated model. Since the interval straddles the threshold, we cannot guarantee that the period is below 1.43 s for all permitted values. The appropriate conclusion is conditional, not a confident pass.
If every permitted value were between 1.410 and 1.420 s, the entire interval would lie below 1.43 s, and the model would support a pass under the supplied assumptions. If every value were above 1.43 s, it would support a fail. This is more useful than comparing only a rounded central estimate.
The example is fictional and not a real device standard. Its mathematical lesson is the power of bounding arguments: when a decision depends on a threshold, check the whole justified interval rather than only a convenient midpoint.
A full mock Paper 2-style modelling task
An invented school activity logs three sets of oscillations. Group A records eight cycles in 8.1 s and twelve cycles in 12.3 s. Group B records five cycles in 7.0 s and fifteen cycles in 21.6 s. First compute A’s pooled period: (8.1 + 12.3)/(8 + 12) = 20.4/20 = 1.02 s. For B, (7.0 + 21.6)/(5 + 15) = 28.6/20 = 1.43 s. Both groups observed twenty cycles in total, though their trials had different lengths.
Now compare the group means: B exceeds A by 0.41 s per cycle. The ratio 1.43/1.02 is approximately 1.40. If both groups had to demonstrate thirty complete cycles at their respective average periods, the ideal extrapolated totals would be 30.6 s and 42.9 s. Label them estimates because we have assumed the periods stay constant.
Finally evaluate a claim: ‘Group B must have used a longer string.’ The timing data alone do not establish what apparatus was used. They establish a difference in observed average period under the stated records. The final sentence should separate mathematical inference from missing scientific context.
How to earn marks through clear working
For every multi-stage rate question, write the defining relationship, identify the total and its denominator, substitute, calculate and interpret. In the 43.4 seconds over thirty cycles example, the working can read ‘mean period = total observed seconds / total observed cycles = 43.4/30 ≈ 1.45 s’. This shows what the number means and is easy to check.
If a later part asks for a percentage increase, carry the unrounded value into that operation where possible and identify the base period. If a graph is involved, label both axes and units before reading slopes. If a bound is involved, write both endpoints rather than mentioning only the best case.
The official syllabus notes that omission of essential working can cost marks. This is a good reason to organise the method, not to fill the page with irrelevant arithmetic. A few explanatory words can show which mathematical idea the student understood.
A five-step self-check before moving on
First, does the recorded time refer to one cycle or several? Second, are the cycle counts the same across the observations being compared? Third, if they differ, have you chosen the average that matches the question’s wording? Fourth, have you retained the correct unit, especially seconds versus milliseconds and period versus frequency? Fifth, does your final sentence state the correct comparison and reference?
Run these checks on the earlier dataset. Ten cycles in 10.1 s correspond to 1.01 s per cycle. Ten cycles in 14.2 s correspond to 1.42 s per cycle. The latter is larger by 0.41 s, about 40.6% relative to the first. The statements depend only on the supplied data, not on a claim about every pendulum.
If you cannot answer any step confidently, practise that one step with new numbers before moving on. Most repeated errors are local and repairable. The point of examination preparation is to build dependable decisions, not merely faster calculations.
Link the reasoning back to earlier learning
The companion Volume 0926 Physics pendulum experiment explains what was physically measured and how to conduct a fair comparison. This Mathematics guide owns the denominator, weighting, rounding and threshold arguments; the two guides complement each other without competing for the same question.
For the Primary-to-Secondary bridge, read the PSLE guide on averages with different group sizes. The principle that different denominators require care continues into G3 rate work. For wider preparation, the Secondary Mathematics mastery-checkpoint guide helps students assess whether the method is stable enough to transfer to new contexts.
The next EMS learning step is communication: explain a numerical result without accidentally changing what the numbers represent.
A study session built around explanations
Spend five minutes converting unlike cycle-count totals into comparable periods. Spend six minutes contrasting an unweighted trial mean with a pooled per-cycle mean. Spend five minutes interpreting one percentage increase and the reverse percentage decrease, naming the base each time. Spend five minutes writing a two-sentence explanation of a bound that straddles a threshold. Use the final five minutes to repair a flawed claim about a length ratio.
These times are a study routine, not official exam time allocation. The aim is to practise the whole sequence: number, denominator, unit, model and conclusion. A learner who can compute but cannot state the comparison has only half the skill. A learner who understands a claim but repeatedly copies the wrong denominator needs targeted arithmetic practice.
Keep a small correction record. Instead of ‘I was careless’, write ‘I averaged raw times from unequal-count trials, although the task asked for pooled period’. A precise diagnosis offers a precise repair.
Frequently asked questions
Is the pendulum a confirmed G3 Mathematics exam question?
No. It is a fictional context for general data, ratio, rate, graph and reasoning skills, not an announced SEC paper.
Can I average the total times when cycle counts differ?
You can average total trial durations if that is what the question asks, but it does not automatically give the mean time per cycle. Convert or pool appropriately.
What is the difference between an unweighted and pooled mean?
An unweighted mean gives each trial estimate equal weight; a pooled per-cycle mean weights each by its cycle count.
Does a bigger period mean bigger frequency?
No. For steady periodic motion, frequency is the reciprocal of period.
Should I round every intermediate answer to three significant figures?
Keep adequate precision through the calculation and use the requested rounding for the final answer.
Does a narrow observed range prove the true value is inside it?
No. The range only describes the sample, not a guaranteed uncertainty interval or confidence statement.
Check the official assessment and continue
Read the SEAB 2027 SEC G3 syllabus list and K310 G3 Mathematics syllabus. The examples above are original illustrations and not official examination questions.