Riordan's age is
13 his brother's age now. In 10 years' time, his age will be
35 that of his brother's. How old is Riordan now?
|
Riordan |
Riordan's brother |
Difference |
Before |
1x1 = 1 u |
3x1 = 3 u |
2x1 = 2 u |
Change |
+ 10 |
+ 10 |
|
After |
3x1 = 3 u |
5x1 = 5 u |
2x1 = 2 u |
The difference in the age between Riordan and Riordan's brother remains unchanged. Make the difference in age the same. LCM of 2 and 2 is 2.
Increase in the age of Riordan
= 3 u - 1 u
= 2 u
2 u = 10
1 u = 10 ÷ 2 = 5
Riordan's age now
= 1 u
= 1 x 5
= 5
Answer(s): 5