Adam and Charlie have some stickers in the ratio of 7 : 3.
When Adam gives away 81 stickers,
the ratio of the stickers becomes 5 : 6.
- How many stickers do they have at first?
- How many stickers do they have in the end?
|
Adam |
Charlie |
Before |
7 x 2 = 14 u |
3 x 2 = 6 u |
Change |
- 81 |
No change |
After |
5 x 1 = 5 u |
6 x 1 = 6 u |
(a)
The number of stickers that Charlie has remains unchanged.
Make the number of stickers that Charlie has the same using LCM of 3 and 6.
LCM of 3 and 6 = 6
Number of stickers that Adam gives away
= 14 u - 5 u
= 9 u
9 u = 81
1 u = 81 ÷ 9 = 9
Number of stickers that they have at first
= 14 u + 6 u
= 20 u
= 20 x 9
= 180
(b)
Number of stickers that they have in the end
= 5 u + 6 u
= 11 u
= 11 x 9
= 99
Answer(s): (a) 180; (b) 99