The ratio of the number of blue stickers to red stickers is 3 : 1.
After Adam buys 20 blue stickers and 40 red stickers,
there is an equal number of blue stickers and red stickers.
How many stickers does Adam have now?
|
Blue |
Red |
Before |
3 u |
1 u |
Change |
+ 20 |
+ 40 |
After |
3 u + 20 |
1 u + 40 |
The number of blue stickers and red stickers are equal in the end.
3 u + 20 = 1 u + 40
3 u - 1 u = 40 - 20
2 u = 20
1 u = 20 ÷ 2 = 10
Number of stickers that Adam has now
= 3 u + 20 + 1 u + 40
= 3 u + 1 u + 20 + 40
= 4 u + 60
= 4 x 10 + 60
= 40 + 60
= 100
Answer(s): 100