Mr Cody is 3 times as old as his cousin, Peter. 6 years ago, the ratio in the age of Mr Cody and Peter was 9 : 2. Find Mr Cody's current age.
| |
Mr Cody |
Peter |
Difference |
| Before |
9x2 =
18 u |
2x2 =
4 u |
7x2 =
14 u |
| Change |
+ 6 |
+ 6 |
|
| After |
3x7 =
21 u |
1x7 =
7 u |
2x7 =
14 u |
The difference in the age of Mr Cody and Peter at first and in the end remains unchanged. Make the difference in age the same. LCM of 7 and 2 is 14.
The increase in the age of Mr Cody and Peter is the same.
Increase in Peter's age
= 7 u - 4 u
= 3 u
3 u = 6
1 u = 6 ÷ 3 = 2
Mr Cody's current age
= 21 u
= 21 x 2
= 42
Answer(s): 42
