1. Convert percentage into fraction. Better to work with.
25% = 1/4
37.5% = 3/8
2. Use guess and check. Draw table. .
Column 1: Boy (name)
Column 2: Age now
Column 3: Age 4 years ago
Column 4: Age 8 years later

Row 1: Wayne
Row 2: Raymond

Steps to trial. Fill in numbers. .
- 1st guess of Wayne's Age Now be 5
- then fill in Wayne's Age 4 years ago (5 - 4 = 1)
- then you can fill in Raymond's Age 4 years ago (4 x 1 = 4)
- then you get Raymond's Age Now (4 + 4 =8)
- fill in both boys for Age 8 years later
(Wayne: 1 + 8 = 9)
(Raymond: 8 + 8 = 16)
- Check: Wayne/Raymond = 9/16
BECAUSE 9/16 is not equals to 3/8, 1st guess is wrong.
THEREFORE repeat steps with 2nd guess (choose 5 or any number less ).