Jack's age is
23 his sister's age now. 20 years ago, his age was
14 that of his sister's. How old is Jack now?
|
Jack |
Jack's sister |
Difference |
Before |
1x1 = 1 u |
4x1 = 4 u |
3x1 = 3 u |
Change |
+ 20 |
+ 20 |
|
After |
2x3 = 6 u |
3x3 = 9 u |
1x3 = 3 u |
The difference in the age between Jack and Jack's sister remains unchanged. Make the difference in age the same. LCM of 3 and 1 is 3.
Increase in the age of Jack
= 6 u - 1 u
= 5 u
5 u = 20
1 u = 20 ÷ 5 = 4
Jack's age now
= 6 u
= 6 x 4
= 24
Answer(s): 24