Part 1: Statistical Knowledge

1. Which measure of centre is usually most suitable for a data set containing an extreme outlier?

Mean

Median

Range

Maximum

2. The number of books read by six students was: 2, 5, 3, 2, 8, 4. What is the mode?

2

3

4

8

3. Which graph is most suitable for displaying the relationship between hours of study and test marks?

Pie graph

Scatter plot

Stem-and-leaf plot

Frequency table

4. A survey asks every fifth student entering the school library to participate. What sampling method is being used?

Simple random sampling

Systematic sampling

Convenience sampling

Census

Part 2: Calculating Statistics

5. The daily temperatures in Ōtautahi over seven days were: 14°C, 17°C, 16°C, 19°C, 15°C, 17°C, 20°C. Calculate the mean, median, mode and range.

6. The times, in minutes, taken by five students to complete a puzzle were 12, 18, 15, 11 and 24. Calculate the mean time.

7. A data set has a minimum of $8, a lower quartile of $12, a median of $15, an upper quartile of $21 and a maximum of $30. Calculate the interquartile range.

8. The mean of four numbers is 12. Three of the numbers are 8, 11 and 15. Find the fourth number.

Part 3: Interpreting Data

9. A school surveys 40 students about their preferred lunchtime activity. Explain one possible source of bias in this survey if students are selected only from the sports field.

10. A scatter plot shows that as weekly exercise time increases, average resting heart rate tends to decrease. Describe the association and explain whether this proves that exercise causes the decrease.