Adam and Bryan have some stickers in the ratio of 2 : 3.
When Adam buys another 51 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?
|
Bryan |
Charlie |
Before |
2 x 2 = 4 u |
3 x 2 = 6 u |
Change |
+ 51 |
No change |
After |
7 x 3 = 21 u |
2 x 3 = 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 2.
LCM of 3 and 2 = 6
Number of stickers that Bryan buys
= 21 u - 4 u
= 17 u
17 u = 51
1 u = 51 ÷ 17 = 3
Number of stickers that they have at first
= 4 u + 6 u
= 10 u
= 10 x 3
= 30
(b)
Number of stickers that they have in the end
= 21 u + 6 u
= 27 u
= 27 x 3
= 81
Answer(s): (a) 30; (b) 81