The ratio of the number of blue stickers to red stickers is 7 : 5.
After Adam buys 20 blue stickers and 80 red stickers,
there is an equal number of blue stickers and red stickers.
How many stickers does Adam have now?
|
Blue |
Red |
Before |
7 u |
5 u |
Change |
+ 20 |
+ 80 |
After |
7 u + 20 |
5 u + 80 |
The number of blue stickers and red stickers are equal in the end.
7 u + 20 = 5 u + 80
7 u - 5 u = 80 - 20
2 u = 60
1 u = 60 ÷ 2 = 30
Number of stickers that Adam has now
= 7 u + 20 + 5 u + 80
= 7 u + 5 u + 20 + 80
= 12 u + 100
= 12 x 30 + 100
= 360 + 100
= 460
Answer(s): 460