The average test score of rsm students in september increased by 10%. in october it increased by another 15%. by what percent did the average score on the test increase during the two months?

The Average test score start = 100%

It increases by 10%: 

100% = 1
10% = 0.10

1 x 0.10 = 0.1
1 + 0.1 = 1.1

It increases by another 15%

1.1 x 0.15 = 0.165
1.1 + 0.165 = 1.265
Remember to move the place value digit to the right two spaces to make it a percentage

126.5% increase is your answer

hope this helps

Im not really sure if you add or something is that all it says