The ratio of the number of green stickers to blue stickers is 5 : 2.
After Adam gives away 65 green stickers and gives away 66 blue stickers,
the ratio becomes of the number of green stickers to blue stickers is 7 : 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 7 = (4) |
Before |
10 u |
5 u |
2 u |
14 u |
Change |
- 130 |
- 65 |
- 66 |
- 462 |
After |
14 p |
7 p |
2 p |
14 p |
5 u - 65 = 7 p --- (1)
2 u - 66 = 2 p --- (2)
Make p the same.
(1) x 2
10 u - 130 = 14 p --- (3)
(2) x 7
14 u - 462 = 14 p --- (4)
(4) = (3)
14 u - 462 = 10 u - 130
14 u - 10 u = 462 - 130
4 u = 332
1 u = 332 ÷ 4 = 83
Number of stickers that Adam has now
= 5 u - 65 + 2 u - 66
= 7 u - 131
= 7 x 83 - 131
= 581 - 131
= 450
Answer(s): 450