The ratio of the number of green stickers to blue stickers is 8 : 1.
After Adam buys another 40 blue stickers and gives away 18 green stickers,
the ratio becomes of the number of green stickers to blue stickers is 3 : 2.
How many stickers does Adam have now?
|
Make p the same (1) x 2 = (3) |
(1) Green |
(2) Blue |
Make p the same (2) x 3 = (4) |
Before |
16 u |
8 u |
1 u |
3 u |
Change |
- 36 |
- 18 |
+ 40 |
+ 120 |
After |
6 p |
3 p |
2 p |
6 p |
8 u + 40 = 3 p --- (1)
1 u - 18 = 2 p --- (2)
Make p the same.
(1)
x 216 u - 36 = 6 p --- (3)
(2)
x 33 u + 120 = 6 p --- (4)
(3) = (4)
16 u - 36 = 3 u + 120
16 u - 3 u = 36 + 120
13 u = 156
1 u = 156 ÷ 13 = 12
Number of stickers that Adam have now
= 8 u + 40 + 1 u - 18
= 8 u + 1 u + 40 - 18
= 9 u + 22
= 9 x 12 + 22
= 108 + 22
= 130
Answer(s): 130