Question

80 95 90 80 100 _ what goes on the blank to get a mean of 90

Answer 1

95.

Explanation:

The are a total of 6 numbers so to make the mean 90 the total must be 6*90 = 540.

So the number in the blank is 540 - (80 + 95+90+80+100)

= 540 - 445

= 95.

Answer 2

95

Explanation:

(80 + 95 + 90 + 80 + 100 + x) / 6= 90

x = 95