Question

I will medal and fan!

Ms Ratchett's math class averaged poorly on a test, so she gave them a retest. If all 30 students in the class scored 10 points higher on the retest, how would the MEAN of the retest scores differ from the MEAN of the scores on the first test?
A) The means would be the same.
B) The mean on the retest would be 3 points higher.
C) The mean on the retest would be 10 points higher.
D) The mean on the retest would be 13 points higher.

Answer 1

I think its C but im not sure

Answer 2

For questions like this, I like to make up numbers for what they don't give you. Let's assume that the first test everyone got a 70. The mean would be 70. Using that lets find the new mean: \[\frac{ 80*30+70*30 }{ 60}=\]

Answer 3

thanks but did you read the answers?

Answer 4

yeah it's c.

Answer 5

Ok, thanks!

Answer 6

np