Mr Mark is 2 times as old as his son, Asher. 30 years ago, the ratio in the age of Mr Mark and Asher was 9 : 2. Find Mr Mark's current age.
|
Mr Mark |
Asher |
Difference |
Before |
9x1 = 9 u |
2x1 = 2 u |
7x1 = 7 u |
Change |
+ 30 |
+ 30 |
|
After |
2x7 = 14 u |
1x7 = 7 u |
1x7 = 7 u |
The difference in the age of Mr Mark and Asher at first and in the end remains unchanged. Make the difference in age the same. LCM of 7 and 1 is 7.
The increase in the age of Mr Mark and Asher is the same.
Increase in Asher's age
= 7 u - 2 u
= 5 u
5 u = 30
1 u = 30 ÷ 5 = 6
Mr Mark's current age
= 14 u
= 14 x 6
= 84
Answer(s): 84