Seth's age is
35 his sister's age now. 10 years ago, his age was
13 that of his sister's. How old is Seth now?
| |
Seth |
Seth's sister |
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 Seth and Seth's sister remains unchanged. Make the difference in age the same. LCM of 2 and 2 is 2.
Increase in the age of Seth
= 3 u - 1 u
= 2 u
2 u = 10
1 u = 10 ÷ 2 = 5
Seth's age now
= 3 u
= 3 x 5
= 15
Answer(s): 15
