Question

What is the interquartile range of the set of data this box-and-whisker plot represents?

Answer 1

3

Explanation:

The interquartile range is where the 2nd and 5th dots are, on the opposite ends of the square, from 15-18.

Answer 2

3

Explanation:

The interquartile range (IQR) is the difference between the upper quartile (Q₃) and the lower quartile (Q₁).

In a box plot:

• The left edge of the box represents the lower quartile.
• The right edge of the box represents the upper quartile.

From inspection of the given box plot:

• lower quartile (Q₁) = 15
• upper quartile (Q₃) = 18

Therefore:

IQR = Q₃ - Q₁

= 18 - 15

= 3

So the interquartile range of the given box plot is 3.