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Year 9 Statistics revision questions

Year 9 is the awkward bridge year: still Key Stage 3 in school life, but already starting GCSE habits. This page gives free Year 9 Statistics practice from GradeNinja's own bank - 54 auto-marked questions across 1 Year 9 topic set.

What Year 9 revision should do

The aim is not to cram GCSE papers early. It is to make the first GCSE topics feel normal: short retrieval practice, clear corrections, and enough repetition that classwork sticks before Year 10 gets busy.

Use these as ten-minute checks after a lesson or before homework. If you miss one, read the explanation, then come back tomorrow and answer it cold.

How GradeNinja pitches it

Year 9 questions are pulled from late Key Stage 3 and foundation GCSE bridge material. They should feel harder than Year 8, but they are not meant to be full Year 11 exam questions.

Year 9 (Starting GCSE) - Practice Mix80 questions

Best way to use this page

Answer first, then reveal. The useful bit is the retrieval attempt, not reading the answer. If a topic keeps going wrong, paste the homework or Google Classroom text into GradeNinja's Classroom import tool and turn it into a focused pack.

Year 9 Statistics practice questions

Real questions from GradeNinja's own bank, with the answer and the explanation the app gives. Tap to reveal.

Question 1 · Year 9 (Starting GCSE) - Practice Mix
What does rs = −1 indicate?
  1. Perfect positive correlation
  2. No correlation
  3. Weak negative correlation
  4. Perfect negative correlation
Show the answer

Perfect negative correlation

rs = −1 means perfect negative correlation: as one variable increases, the other decreases in perfect rank order.

Question 2 · Year 9 (Starting GCSE) - Practice Mix
A fair coin is flipped 10 times. What is the expected number of heads?
  1. 10 x 0.5 = 5
  2. 10 / 0.5 = 20
  3. 0.5 / 10 = 0.05
  4. 10 + 0.5 = 10.5
Show the answer

10 x 0.5 = 5

Expected number of successes = n x p = 10 x 0.5 = 5.

Question 3 · Year 9 (Starting GCSE) - Practice Mix
A pie chart has a sector of 90°. What fraction of the total does this sector represent?
  1. One half
  2. One quarter
  3. One third
  4. Three quarters
Show the answer

One quarter

A full circle = 360°. 90° ÷ 360° = 1/4. So this sector represents one quarter of the total.

Question 4 · Year 9 (Starting GCSE) - Practice Mix
A bag contains 3 red, 4 blue, and 5 green counters. One is chosen at random. What is P(green)?
  1. 1/4
  2. 5/12
  3. 1/3
  4. 5/7
Show the answer

5/12

Total counters = 3+4+5 = 12. P(green) = 5/12.

Question 5 · Year 9 (Starting GCSE) - Practice Mix
Which formula gives the standard deviation of a data set?
  1. sqrt(Σ(x - mean)² / n)
  2. Σ(x - mean) / n
  3. (maximum - minimum) / 2
  4. Σx / n
Show the answer

sqrt(Σ(x - mean)² / n)

Standard deviation is the square root of the mean of the squared deviations from the mean (the variance).

Question 6 · Year 9 (Starting GCSE) - Practice Mix
Spearman's rank correlation coefficient (rs) has a value of +1. What does this mean?
  1. No correlation
  2. Perfect negative correlation
  3. Perfect positive correlation
  4. Moderate positive correlation
Show the answer

Perfect positive correlation

rs = +1 means perfect positive correlation: as one variable increases, the other increases in perfect rank order.

Question 7 · Year 9 (Starting GCSE) - Practice Mix
A histogram bar covers the class 5 to 10 with frequency density 6. What is the frequency for this class?
  1. 1.2
  2. 30
  3. 11
  4. 60
Show the answer

30

Frequency = Frequency Density x Class Width = 6 x 5 = 30.

Question 8 · Year 9 (Starting GCSE) - Practice Mix
A 3-point moving average is calculated for the data: 4, 8, 6, 10, 12. What is the second moving average value?
  1. 6
  2. 7
  3. 8
  4. 9
Show the answer

8

The second 3-point moving average uses values 8, 6, 10: (8 + 6 + 10) ÷ 3 = 24 ÷ 3 = 8.

Question 9 · Year 9 (Starting GCSE) - Practice Mix
What is the "mean" of a data set?
  1. The middle value when data is ordered
  2. The most frequently occurring value
  3. The sum of all values divided by the number of values
  4. The difference between the highest and lowest values
Show the answer

The sum of all values divided by the number of values

The mean is calculated by adding all values together and dividing by the total number of values; it is sensitive to extreme outliers.

Question 10 · Year 9 (Starting GCSE) - Practice Mix
What is the purpose of calculating a moving average for a time series?
  1. To increase the range of the data
  2. To smooth out short-term fluctuations and reveal the underlying trend
  3. To find the modal value across all time periods
  4. To show seasonal variation more clearly
Show the answer

To smooth out short-term fluctuations and reveal the underlying trend

Moving averages smooth out random short-term fluctuations (noise) and seasonal effects, making the underlying long-term trend easier to identify.

Question 11 · Year 9 (Starting GCSE) - Practice Mix
A bag contains 3 red, 5 blue and 2 green counters. A counter is chosen at random. What is the probability it is red?
  1. 3/5
  2. 3/8
  3. 3/10
  4. 1/3
Show the answer

3/10

P(red) = favourable outcomes ÷ total outcomes = 3 ÷ (3+5+2) = 3/10.

Question 12 · Year 9 (Starting GCSE) - Practice Mix
An item cost £40 in the base year and £50 this year. What is the price index number this year, taking the base year as 100?
  1. 110
  2. 120
  3. 125
  4. 150
Show the answer

125

Index = (current value / base value) x 100 = (50 / 40) x 100 = 125.

Question 13 · Year 9 (Starting GCSE) - Practice Mix
The mean of the values 3, 7, 2, 9, 4 is:
  1. 4
  2. 5
  3. 7
  4. 9
Show the answer

5

Mean = (3 + 7 + 2 + 9 + 4) ÷ 5 = 25 ÷ 5 = 5.

Question 14 · Year 9 (Starting GCSE) - Practice Mix
What does "random sampling" mean?
  1. Choosing whoever is most convenient
  2. Every member of the population has an equal chance of selection
  3. Selecting people based on specific characteristics
  4. Choosing every tenth person on a list
Show the answer

Every member of the population has an equal chance of selection

In random sampling, every individual in the population has an equal probability of being selected, reducing bias in the sample.

Question 15 · Year 9 (Starting GCSE) - Practice Mix
The data set is: 2, 4, 6, 8, 10. What is the mean?
  1. 5
  2. 6
  3. 7
  4. 8
Show the answer

6

Sum = 2+4+6+8+10 = 30. Mean = 30/5 = 6.

Question 16 · Year 9 (Starting GCSE) - Practice Mix
Which of the following describes the normal distribution?
  1. Bell-shaped, symmetric about the mean
  2. Skewed to the right, with a long right tail
  3. Uniform, with all values equally likely
  4. U-shaped, with high frequency at extremes
Show the answer

Bell-shaped, symmetric about the mean

The normal distribution is a symmetric, bell-shaped distribution. The mean, median, and mode all coincide at the centre.

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Common questions

Are these Year 9 Statistics questions GCSE level?

They are bridge questions: harder than early Key Stage 3, but not pitched as full Year 11 GCSE exam papers. The point is to prepare the habits and core knowledge early.

Can I use Google Classroom homework with GradeNinja?

Yes. Use Classroom import in the app: paste the Google Classroom post, homework email or assignment brief and it turns the topics into practice questions and flashcards.

How often should a Year 9 revise Statistics?

Short and often. Ten minutes after a lesson or a few times a week is more useful than one long session before a test.

Is GradeNinja free for Year 9?

Yes, signing up is free. GradeNinja has Year 9 bridge content plus the wider question bank across 28 subjects.

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