Question

John scored 75, 82, 66, and 78 on his history tests. What score must John get on his next test in order to have a mean score of 76?

Answer 1

[75 + 82 + 66 + 78 + x ] / 5 = 76

301 + x = 380

x = 79

Answer 2

In the next test John must get
`79`

Explanation:

Let

x------> the score in the next test

we know that

The formula to calculate the mean is the sum of the scores divided by the number of test

so

`76=(75+82+66+78+x)/(5)`

Solve for x

`76=(301+x)/(5)\\ \\x=76*5-301\\ \\x=79`