The ratio of the number of red stickers to green stickers is 9 : 4.
After Adam buys 10 red stickers and 20 green stickers,
there is an equal number of red stickers and green stickers.
How many stickers does Adam have now?
| |
Red |
Green |
| Before |
9 u |
4 u |
| Change |
+ 10 |
+ 20 |
| After |
9 u + 10 |
4 u + 20 |
The number of red stickers and green stickers are equal in the end.
9 u + 10 = 4 u + 20
9 u - 4 u = 20 - 10
5 u = 10
1 u = 10 ÷ 5 = 2
Number of stickers that Adam has now
= 9 u + 10 + 4 u + 20
= 9 u + 4 u + 10 + 20
= 13 u + 30
= 13 x 2 + 30
= 26 + 30
= 56
Answer(s): 56
