Adam is 10 years old. The total age of Adam and Bryan is 70 years. How many years' time will the ratio of Adam's age to Bryan's age be 1 : 3?
| |
Adam |
Bryan |
Total |
Difference |
| Before |
10 |
60 |
70 |
50 |
| Change |
+ ? |
+ ? |
|
|
| After |
1 u |
3 u |
|
2 u |
Bryan's age
= 70 - 10
= 60
Difference in the age between Adam and Bryan
= 60 - 10
= 50
Difference in the age between Adam and Bryan in units
= 3 u - 1 u
= 2 u
2 u = 50
1 u = 50 ÷ 2 = 25
Adam's age now = 10
Adam's age after = 1 u = 1 x 25 = 25
Number of years' time
= 25 - 10
= 15
Answer(s): 15
