The test scores for 9 students on the Unit 1 test were 35, 25, 50, 95, 80, 60, 45, 100, and 90. What is the value of the third quartile for this data set?
A. 85
B. 90
C. 92.5
D. 95

Question

The test scores for 9 students on the Unit 1 test were 35, 25, 50, 95, 80, 60, 45, 100, and 90. What is the value of the third quartile for this data set?
	A.	85
	B.	90
	C.	92.5
	D.	95

anonymous · Answer

i made the graph ... http://mrnussbaum.com/graph/bw/

anonymous · Answer

@whpalmer4

whpalmer4 · Answer

Yeah, that's just the link to the graphing site, it doesn't show your graph...

anonymous · Answer

oh, well thats dumb then, i think i got it though. i just wanted to double check, cause ive never done a box or whiskey plot before! sorry.

anonymous · Answer

by the way, that last question didnt give me the right answer on that assignment, i was pretty upset. ill have to talk to someone about that.

anonymous · Answer

First you'll want to find the median, so order the data:
25, 35, 45, 50, 60, 80, 90, 95, 100
 x    x     x    x   60    x    x    x     x

Our median is 60. The third quartile is the median of the upper half. So, we take all the data above 60, and find the median:
80, 90, 95, 100
 x   90  95    x
Median=Average of 90 and 95=92.5

anonymous · Answer

oh!! thank you, i thought i knew it but i was wrong, i didnt know its the median of the upper half, i thought it was just whatever the whiskey ended on.

anonymous · Answer

The third line in the plot should be the 3rd quartile. The actual "whiskers" end at the highest and lowest data values though.

anonymous · Answer

well thanks!

anonymous · Answer

You're welcome, glad I could help.