Question

Mr. Evans displays the test scores of his first period class in the box plot below.

The test scores from Mr. Evan's 3rd period class result in a 1st Quartile of 78 and an IQR that is one-third the IQR of his first period class. What value represents the value of the 3rd quartile of the scores from 3rd period?

Answer 1

The IQR of the first period is 15. The IQR of the third period is 1/3 that, 5*(1/3) is equal to 5.

For the third period, Q1 is 78. The expression for Q3 is Q1+IQR

Therefore, 78+5 = 83

Q3 of the third period is 83

Answer 2

Explanation:

Median is the middle entry when arranged in ascending or descending order.Q1 can be mentioned as the median of first entry to median, when arranged inascending order. Similarly Q3 is the median of the entries from median to end

Q1=78

IQR=Q3-Q1=5

Q3=78+5=83

Hence answer is 83