MATH 7th GRADE
posted by MATH HELP PLEASE .
Vicki measured the length of 8 leaves. The lengths were 10 cm, 12 cm, 15 cm, 15 cm, 19 cm, 11 cm, 18 cm, and 15 cm.
What is the interquartile range of Vicki's data? answer choices are:
a. 1
b. 3
c. 5
d. 6
I chose 5 and it says that 6 is the correct answer. Can you please show me why?
I have Q1 = 11.5 and Q3 = 16.5.
Then 16.5  11.5 = 5 (So the IQR = 5)

put them in order:
10, 11, 12, 15,15,15,18,19 8 data
divide them into quarters.
10,11
12,15
15,15
18,16
I agree with you. 
I think it is 12,15