Charlie and Bryan have some stickers in the ratio of 7 : 8.
When Charlie gives away 99 stickers,
the ratio of the stickers becomes 5 : 7.
- How many stickers do they have at first?
- How many stickers do they have in the end?
|
Charlie |
Bryan |
Before |
7 x 7 = 49 u |
8 x 7 = 56 u |
Change |
- 99 |
No change |
After |
5 x 8 = 40 u |
7 x 8 = 56 u |
(a)
The number of stickers that Bryan has remains unchanged.
Make the number of stickers that Bryan has the same using LCM of 8 and 7.
LCM of 8 and 7 = 56
Number of stickers that Charlie gives away
= 49 u - 40 u
= 9 u
9 u = 99
1 u = 99 ÷ 9 = 11
Number of stickers that they have at first
= 49 u + 56 u
= 105 u
= 105 x 11
= 1155
(b)
Number of stickers that they have in the end
= 40 u + 56 u
= 96 u
= 96 x 11
= 1056
Answer(s): (a) 1155; (b) 1056