Adam has 90 red stickers and 250 green stickers.
After buying the same number of stickers,
the ratio of the red stickers and the green stickers becomes 3 : 5.
How many stickers does he buy?
|
Red |
Green |
Difference |
Before |
90 |
250 |
160 |
Change |
+ ? |
+ ? |
|
After |
3 u |
5 u |
2 u |
At first
Difference in the number of stickers
= 250 - 90
= 160
In the end
Number of red stickers = 3 u
Number of green stickers = 5 u
Difference in the number of stickers in units
= 5 u - 3 u
= 2 u
The difference in the number of stickers between the red stickers and the green stickers remains unchanged.
2 u = 160
1 u = 160 ÷ 2 = 80
Number of red stickers that Adam buys
= 3 u - 90
= 3 x 80 - 90
= 240 - 90
= 150
Total number of stickers that Adam buys
= 2 x 150
= 300
Answer(s): 300