Question

7.

If twenty-one more than a fifth of a number is equal to two times the quantity of
three less than that number, what is the number?

Answer 1

The number is 15.

Explanation:

Let n be the number.

`(1)/(5) n + 21 = 2(n - 3)`

`n + 105 = 10(n - 3)`

`n + 105 = 10n - 30`

`9n = 135`

`n = 15`