Question

12.5,−10,−7.5,x; The mean is 11.5.

Answer 1

x = 51

Explanation:

the mean is calculated as

mean =
`(sum)/(count)`

here mean = 11.5 , then

`(12.5-10-7.5 +x)/(4)` = 11.5 ( multiply both sides by 4 to clear the fraction )

- 5 + x = 46 ( add 5 to both sides )

x = 51