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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

User Adrichman
by
2.9k points

2 Answers

1 vote

Answer:

26.5%

Explanation:

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User Kukuh Tw
by
3.0k points
5 votes

Answer:

26.5%

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\%

User DIG
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3.5k points