Answer:
14
Explanation:
The interquartile range is the value of quartile 3 minus quartile 1.
The "box" part of this diagram has 3 lines, the left most, the middle, and the rightmost.
The leftmost line is Quartile 1. The right most is Quartile 3.
Hence
interquartile range = quartile 3 - quartile 1
Looking at the box plot, we can see that each small line in the number line is 2 units.
The leftmost line (quartile 1 ) is at 1 unit left of 30, so that is 30 -2 = 28
The rightmost line (quartile 3) is at 1 unit right of 40, so that is 40 + 2 = 42
Hence,
Interquartile range = 42 - 28 = 14