Question

What number and 12 have an average of 27?

Answer 1

`\boxed{Number \: that \: give \: average \: of \: 27 \: with \: 12 \: is \: 42}`

Explanation:

Let the number be 'x'

`= > (x + 12)/(2) = 27 \\ \\ = > x + 12 = 27 * 2 \\ \\ = > x + 12 = 54 \\ \\ = > x = 54 - 12 \\ \\ = > x = 42`