The ratio of the number of red stickers to green stickers is 3 : 1.
After Adam buys 20 red stickers and 60 green stickers,
there is an equal number of red stickers and green stickers.
How many stickers does Adam have now?
|
Red |
Green |
Before |
3 u |
1 u |
Change |
+ 20 |
+ 60 |
After |
3 u + 20 |
1 u + 60 |
The number of red stickers and green stickers are equal in the end.
3 u + 20 = 1 u + 60
3 u - 1 u = 60 - 20
2 u = 40
1 u = 40 ÷ 2 = 20
Number of stickers that Adam has now
= 3 u + 20 + 1 u + 60
= 3 u + 1 u + 20 + 60
= 4 u + 80
= 4 x 20 + 80
= 80 + 80
= 160
Answer(s): 160