Adam is 18 years old. The total age of Adam and Bryan is 72 years. How many years ago was the ratio of Adam's age to Bryan's age 1 : 7?
|
Adam |
Bryan |
Total |
Difference |
Before |
1 u |
7 u |
|
6 u |
Change |
+ ? |
+ ? |
|
|
After |
18 |
54 |
72 |
36 |
Bryan's age
= 72 - 18
= 54
Difference in the age between Adam and Bryan
= 54 - 18
= 36
To find the number of years ago for the ratio of Adam's age to Bryan's age to be 1 : 7.
Adam's age = 1 u
Bryan's age = 7 u
Difference in the age
= 7 u - 1 u
= 6 u
6 u = 36
1 u = 36 ÷ 6 = 6
Adam's age then = 1 u = 6
Adam's age now = 18
Number of years ago
= 18 - 6
= 12
Answer(s): 12