Question

The average of 1/5 and a number is 1/4 .Find the number.

Answer 1

Let the number be x
$( \frac{1}{5} + x) \div 2 = \frac{1}{4} \\ ( \frac{1}{5} + x) = \frac{1}{2} \\ x = \frac{1}{2} - \frac{1}{5} \\ x = \frac{5 - 2}{10} \\ x = \frac{3}{10}$