Question

Use the box-and-whisker plot shown to answer the following question.

What is the interquartile range?

Answer 1

6?.

Answer 2

find the median of this set of numbers. Remember, the median is the value exactly in the middle of an ordered set of numbers.

Answer 3

11.5?
9?

Answer 4

the median is 11.5
now find the median of the set of numbers to the left of the median. This is the median of the scores less than the median of all scores, and therefore is the lower quartile.

Answer 5

8

Answer 6

11.5?

Answer 7

its actually 8.75 because when you cross off the pairs you get to 8 and 9.5 and you had to find half of that. so 8.5 is the lower quartile

Answer 8

ok..
4?

Answer 9

oh ok

Answer 10

now you have to find the median of the set of numbers to the right

Answer 11

15?

Answer 12

this is the upper quartile. its the same situation with the lower quartile where you have a whole number and a decimal ( 13.5 and 15) so you add them together and divide by two which yeilds 14.25. this is the upper quartile

Answer 13

ok..

Answer 14

The interquartile range is the difference between the upper quartile and the lower quartile. In our case the IQR 14.25-8.75=5.5

Answer 15

ya ok

Answer 16

so its 5.5?? i thought it was 6.

Answer 17

yeah you were close :)
good luck with any other questions