David is 24 years older than his son. 2 years from now, his son will be
13 of his age while his niece will be
13 of his son. Express his niece’s present age as a fraction of David's present age. Leave your answer in its simplest form.
| |
David |
David's son |
David's niece |
Difference between
David and David's son |
| Before |
9 u - 2 |
3 u - 2 |
1 u - 2 |
24 |
| Change |
+ 2 |
+ 2 |
+ 2 |
|
After
|
3x3 |
1x3 |
|
|
| |
3x1 |
1x1 |
|
Comparing David, his son and his niece
in the end |
9 u |
3 u |
1 u |
6 u |
The repeated identity is the age of David's son. LCM of 1 and 3 is 3.
The difference in age between David and David's son remains unchanged.
Difference in age between David and David's son
= 9 u - 3 u
= 6 u
6 u = 24
1 u = 24 ÷ 6 = 4
His niece's present age
= 1 u - 2
= 1 x 4 - 2
= 4 - 2
= 2
David's present age
= 9 u - 2
= 9 x 4 - 2
= 36 - 2
= 34
His niece's present age as a fraction of David's present age
=
234=
117 Answer(s):
117 
