Daily Practice · Foundation
September 2017 5-a-day
Printing for a group?
The batch download puts all 2 tiers' September 2017 sheets in a single PDF, each tier behind its own divider page - 60 sheets in one file.
Every sheet in September 2017
The same date always regenerates the same five questions, so a sheet you print today is the sheet a classmate prints tomorrow.
- 1st September 2017A bag has 3 red, 4 green and 5 blue balls (12 total). One ball is removed at random and is blue. A second ball is then removed. Find P(second ball is red given the first ball was blue).
- 2nd September 2017A 3D pie chart is used to show market share. Explain why 3D charts can be misleading.
- 3rd September 2017A table has class intervals with frequency x midpoint totals of 45, 120, 90 and frequencies 5, 8, 6. Find the estimated mean.
- 4th September 2017Explain why a pilot survey should be carried out before the full survey is sent out.
- 5th September 2017Find the 4-point moving average of 12, 16, 20, 10.
- 6th September 2017P(rain) = 0.3 and P(snow) = 0.05 on a given day, and rain and snow are mutually exclusive that day. Find P(rain or snow).
- 7th September 2017Using the same histogram, how many students scored between 10 and 30 marks?
- 8th September 2017A box plot has lower quartile 10 and upper quartile 22. Find the interquartile range.
- 9th September 2017The heights (cm) of 6 plants are: 15, 18, 16, 14, 17, 150. Find the mean of the remaining values after removing the outlier.
- 10th September 2017Explain why a crude rate is more useful than a raw total, such as the total number of deaths, when comparing two towns of different sizes.
- 11th September 2017A factory has 400 workers: 160 in production, 120 in packing and 120 in admin. A stratified sample of 50 workers is needed. Find how many should be sampled from packing.
- 12th September 2017Using the same table (0:4, 1:10, 2:4, 3:2), find the mean number of siblings.
- 13th September 2017The mean rainfall in April was 45 mm with a range of 20 mm; in May it was 45 mm with a range of 8 mm. Compare April and May.
- 14th September 2017A cost index for electricity, relative to the same base year, was 120 in 2021 and 150 in 2023. Find the percentage increase in the cost of electricity from 2021 to 2023 (not from the base year).
- 15th September 2017The probability that a train is late is 0.15. Out of 200 trains, how many would you expect to be late?
- 16th September 2017The probability that a machine produces a faulty item is 0.04. Out of 300 items, how many would you expect to be faulty?
- 17th September 2017A box has 3 faulty bulbs out of 10. Two bulbs are chosen without replacement. Find the probability at least one is faulty.
- 18th September 2017In a pyramid, the bars for ages 65+ are unusually long compared with younger age bands. Give one possible reason.
- 19th September 2017A data set has mean 12, median 12, mode 12. Describe its skew.
- 20th September 2017A sample of 80 light bulbs from a batch of 2000 found 4 were faulty. Estimate the number of faulty bulbs in the whole batch.
- 21st September 2017The mean of 6 numbers is 15. Five of the numbers are 10, 12, 14, 18, 20. Find the sixth number.
- 22nd September 2017State one advantage of random sampling.
- 23rd September 2017What is meant by a control variable?
- 24th September 2017Values of 12, 18, 25, 31, 9, 22, 15 are grouped using intervals 0 <= x < 10, 10 <= x < 20, 20 <= x < 30, 30 <= x < 40. State the frequency of the interval 10 <= x < 20.
- 25th September 2017A pie chart shows four categories with angles 90, 120, 60 and x degrees. Find x.
- 26th September 2017Events A and B are mutually exclusive with P(A) = 0.3 and P(B) = 0.25. Find P(A or B).
- 27th September 2017Explain why estimating a y-value for x = 50 would be unreliable if all the plotted data only covers x-values from 0 to 20.
- 28th September 2017Two variables have a correlation coefficient close to 0. What does this suggest?
- 29th September 2017The Spearman's rank correlation coefficient between temperature and ice cream sales for 8 days is rs = 0.95. Describe the correlation.
- 30th September 2017A pilot survey shows that many respondents left a question blank. What might this suggest about the question?