Question

after 15 years Mona will be 5 times as old as she was 5 years ago determine present age

Answer 1

Let her present aage be x
After 15 years she will be five times old as she was 5 years ago,
So, , according to the question
x + 15 = 5( x - 5 )
x + 15 = 5x - 25
x + 15 + 25 = 5x
5x - x = 40
4x = 40
x = 40 ÷ 4 = 10