Question

Last semester, Aaron earned an average score of 90 points on math tests. So far this semester, his average score is 10% lower. What is the average of Aaron's scores this semester?

Answer 1

81 points

Explanation:

First semester . Aaron earned 90 points

Second sementer his average score is 10% lower which 10% of 90 points

To find 10%

10×90/100= 9 ,

10% of 90 is 9

Then subtract yhat from 90 points

90-9 =81

The average score is 81points

Answer 2

He average for this semester so far is 81 points.

Explanation:

Since his score is 10% lower this semester than last semester, then he present score is 100% from the prior semester minus 10%, which equals to 90% of the previous semester. In order to calculate that percentage we can use a rule of three as shown below:

90 points -> 100%

x points -> 90%

100*x = 90*90

x = 8100/100 = 81

He average for this semester so far is 81 points.