Question

20 POINTS
you scored 83, 96, and 88 on three of your math tests. write and solve an equation to find the score you need on the fourth test so that your mean test score is 90.
please explain and show work!

Answer 1

83 + 96 + 88 = 267

267 / 3 = 89

(89 + x) / 2 = 90

Multiply both sides by 2.

89 + x = 180

Subtract 180 - 89.

x = 91