The ratio of the number of blue stickers to green stickers is 5 : 3.
After Adam gives away 20 blue stickers and gives away 33 green stickers,
the ratio becomes of the number of blue stickers to green stickers is 9 : 4.
How many stickers does Adam have now?
|
Make p the same (1) x 4 = (3) |
(1) Blue |
(2) Green |
Make p the same (2) x 9 = (4) |
Before |
20 u |
5 u |
3 u |
27 u |
Change |
- 80 |
- 20 |
- 33 |
- 297 |
After |
36 p |
9 p |
4 p |
36 p |
5 u - 20 = 9 p --- (1)
3 u - 33 = 4 p --- (2)
Make p the same.
(1) x 4
20 u - 80 = 36 p --- (3)
(2) x 9
27 u - 297 = 36 p --- (4)
(4) = (3)
27 u - 297 = 20 u - 80
27 u - 20 u = 297 - 80
7 u = 217
1 u = 217 ÷ 7 = 31
Number of stickers that Adam has now
= 5 u - 20 + 3 u - 33
= 8 u - 53
= 8 x 31 - 53
= 248 - 53
= 195
Answer(s): 195