Paper 1 · November 2020 · Descriptive Statistics

The times to the nearest minute taken by 12 students to complete a task are: 43, 45, 46, 42, 48, 42, 46, 55, 47, 42, 41, 44. What is the interquartile range (Q3 minus Q1) of these times, in minutes?

A3.5

B4.0

C4.5

D5.5

Explanation

Sorted: 41, 42, 42, 42, 43, 44, 45, 46, 46, 47, 48, 55. Q1 is the median of the lower 6 values, (42+42)/2 = 42; Q3 is the median of the upper 6 values, (46+47)/2 = 46.5. IQR = 46.5 - 42 = 4.5.

Derived from ZIMSEC Statistics Paper 1, November 2020, Q2

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