Adam and Bryan have some stickers in the ratio of 5 : 3.
When Adam buys another 77 stickers,
the ratio of the stickers becomes 7 : 2.
- How many stickers do they have at first?
- How many stickers do they have in the end?
|
Charlie |
Bryan |
Before |
5 x 2 = 10 u |
3 x 2 = 6 u |
Change |
+ 77 |
No change |
After |
7 x 3 = 21 u |
2 x 3 = 6 u |
(a)
The number of stickers that Bryan has remains unchanged.
Make the number of stickers that Bryan has the same using LCM of 3 and 2.
LCM of 3 and 2 = 6
Number of stickers that Charlie buys
= 21 u - 10 u
= 11 u
11 u = 77
1 u = 77 ÷ 11 = 7
Number of stickers that they have at first
= 10 u + 6 u
= 16 u
= 16 x 7
= 112
(b)
Number of stickers that they have in the end
= 21 u + 6 u
= 27 u
= 27 x 7
= 189
Answer(s): (a) 112; (b) 189