Adam and Bryan have some stickers in the ratio of 3 : 5.
When Adam buys another 32 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 |
3 x 7 = 21 u |
5 x 7 = 35 u |
Change |
+ 32 |
No change |
After |
5 x 5 = 25 u |
7 x 5 = 35 u |
(a)
The number of stickers that Bryan has remains unchanged.
Make the number of stickers that Bryan has the same using LCM of 5 and 7.
LCM of 5 and 7 = 35
Number of stickers that Charlie buys
= 25 u - 21 u
= 4 u
4 u = 32
1 u = 32 ÷ 4 = 8
Number of stickers that they have at first
= 21 u + 35 u
= 56 u
= 56 x 8
= 448
(b)
Number of stickers that they have in the end
= 25 u + 35 u
= 60 u
= 60 x 8
= 480
Answer(s): (a) 448; (b) 480