Question

The highest temperatures measured at Death Valley, California, from 1995 to 2004 are given as a dataset.

127, 125, 125, 129, 123, 126, 127, 128, 128, 125

Find the range and the interquartile range of the dataset. tell me how to get this

Answer 1

First sort the data in ascending order:
123, 125, 125, 125, 126, 127, 127, 128, 128, 129

Range:
- Range = max − min = 129 − 123 = 6.

Interquartile range (IQR):
- n = 10 (even), so split the data into lower half (first 5) and upper half (last 5):
- Lower half: 123, 125, 125, 125, 126 → median of this half (Q1) is the middle value = 125.
- Upper half: 127, 127, 128, 128, 129 → median of this half (Q3) is the middle value = 128.
- IQR = Q3 − Q1 = 128 − 125 = 3.

Answers: Range = 6; IQR = 3.