Question

find a number which when multipled by 5 is increased by 80

Answer 1

16 ×5=80 so the answer is 16

Answer 2

Let the required number be x
When number is multiplied by 5, the result is 5x.
Also when the number is multiplied by 5, the number increases by 80.
So, 5x=x+80
4x=80
Therefore, x=20.

The required number is 20.