Question

can someone please help me to find the interquartile range of 6,10,12,4,3,7,15,20

Answer 1

first sort the numbers

Answer 2

from least to greatest

Answer 3

what do you get when you do this

Answer 4

so it would be 3,4,6,7,10,12,15,20

Answer 5

good it's 3, 4, 6, 7, 10, 12, 15, 20

Answer 6

now start at each endpoint and cross out the pair of outermost terms

so start with

3, 4, 6, 7, 10, 12, 15, 20

and cross out 3 and 20 to get

4, 6, 7, 10, 12, 15

Answer 7

repeat the last step and cross out 4 and 15

6, 7, 10, 12

Answer 8

cross out the 6 and 12 to get

7, 10

Answer 9

the middle most value will be between 7 and 10

so the median is (7+10)/2 = 17/2 = 8.5

Answer 10

now we have this data set

3, 4, 6, 7, 10, 12, 15, 20

which has a median of 8.5

break the data set into two halves like this

3, 4, 6, 7
10, 12, 15, 20

and find the median of the lower and upper halves