Andy is 11 years older than Carl. 9 years ago, the sum of their age was 73. How old is Carl now?
| |
Andy |
Carl |
Difference |
Total |
| Before |
1 u + 11 |
1 u |
11 |
73 |
| Change |
+ 9 |
+ 9 |
|
+ 18 |
| After |
1 u + 20 |
1 u + 9 |
11 |
2 u + 29 |
The difference in the age between Andy and Carl remains unchanged.
Carl's current age = 1 u
Andy's current age = 1 u + 11
Combined age of Andy and Johny 9 years ago
= 1 u + 1 u + 11
= 2 u + 11
2 u + 11 = 73
2 u = 73 - 11
2 u = 62
1 u = 62 ÷ 2 = 31
Carl's current age
= 1 u + 9
= 31 + 9
= 40
Answer(s): 40
