Question

Miguel has scored 70, 60, and 77 on his previous three tests. What score does he need on his next test so that his average (mean) is 70?

Answer 1

73

Explanation:

Call the unknown test score x.

Add up the test scores.

70+60+77+x

divide by 4, and we want that to equal 70.

So the equation is:

(70+60+77+x)/4 = 70

Solve for x

70+60+77+x = 280

x= 280-70-60-77

x = 73