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Laura has scored 75, 85, 81, 67, and 91 on her previous five tests. What score does she need on her next test so that her average (mean) is 77?

2 Answers

3 votes

Answer:

63

Explanation:

your equation should look like (75+85+81+67+91+x) รท6 = 77 first you multiply 6 to both sides. then you subtract all your previous numbers from 462 (the product of 6 and 77) and you should end up with 63

User Thor Correia
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1 vote
The answer is 63

You start off with 5 scores but you want to find the sixth score. And also you need the average to be 77. So you can set up the equation as (75+85+81+67+91+x)/6=77. Then you can solve the equation. Start by multiplying both sides by 6 so the equation looks like 75+85+81+67+91+x=462. If you take all the numbers on the left and add them together you will get 399+x=462. Finally, you subtract the 399 from both sides. This will leave you with x=63. So the answer is 63.
User Bcr
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