Charlie is 30 years older than his daughter. 3 years from now, his daughter will be
13 of his age while his son will be
35 of his daughter. Express his son’s present age as a fraction of Charlie's present age. Leave your answer in its simplest form.
|
Charlie |
Charlie's daughter |
Charlie's son |
Difference between Charlie and Charlie's daughter |
Before |
15 u - 3 |
5 u - 3 |
3 u - 3 |
30 |
Change |
+ 3 |
+ 3 |
+ 3 |
|
After
|
3x5 |
1x5 |
|
|
|
5x1 |
3x1 |
|
Comparing Charlie, his daughter and his son in the end |
15 u |
5 u |
3 u |
10 u |
The repeated identity is the age of Charlie's daughter. LCM of 1 and 5 is 5.
The difference in age between Charlie and Charlie's daughter remains unchanged.
Difference in age between Charlie and Charlie's daughter
= 15 u - 5 u
= 10 u
10 u = 30
1 u = 30 ÷ 10 = 3
His son's present age
= 3 u - 3
= 3 x 3 - 3
= 9 - 3
= 6
Charlie's present age
= 15 u - 3
= 15 x 3 - 3
= 45 - 3
= 42
His son's present age as a fraction of Charlie's present age
=
642=
17 Answer(s):
17