Question

Chris has scored 78, 61, and 91 on his previous three tests. What score does he need on his next test so that his average (mean) is 78?

Answer 1

(78+61+91+x)/4=78
Rearrange So
(230+x)= 78 x 4
230 + x = 312
x = 312-230
X= 82
Chris need to score 82