Question

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? PLEASE HELP I NEED THE ANSWER QUICK

Answer 1

Answer:

26.5%

Step-by-step explanation:

Increasing  Percentages

When sequential percentages increasing are computed, each increase applies to the previous result, instead of the first quantity. That is why sometimes the final results may be confusing. For example, increasing 10% and then 15% will not be the same as increasing a total of 25%.

The average test scores of RSM students first increased by 10%. It means that some quantity C increased by

$10C/100=0.1C$

Now the average test scores are

$C+0.1C=1.1C$

A new increasing occurred by 15%, and the previous quantity must be multiplied by 1.15, so the final average test scores are

$1.15(1.1C)=1.265C$

It means that the total increasing was $100(1.265-1)=26.5\%$