Question

On his first three tests, Ken scored 83,79, and 96. What score must he get on his fourth test to have an average (mean) of

80 for all four tests?​

Answer 1

62

Explanation:

average =
`(totalscore)/(count)`

Let x represent his fourth score, then

`(83+79+96+x)/(4)` = 80, that is

`(258+x)/(4)` = 80 ( multiply both sides by 4 )

258 + x = 320 ( subtract 258 from both sides )

x = 62

He must obtain a score of 62 in his fourth test