The ratio of the number of green stickers to red stickers is 3 : 2.
After Adam gives away 26 green stickers and gives away 84 red stickers,
the ratio becomes of the number of green stickers to red stickers is 7 : 3.
How many stickers does Adam have now?
|
Make p the same (1) x 3 = (3) |
(1) Green |
(2) Red |
Make p the same (2) x 7 = (4) |
Before |
9 u |
3 u |
2 u |
14 u |
Change |
- 78 |
- 26 |
- 84 |
- 588 |
After |
21 p |
7 p |
3 p |
21 p |
3 u - 26 = 7 p --- (1)
2 u - 84 = 3 p --- (2)
Make p the same.
(1) x 3
9 u - 78 = 21 p --- (3)
(2) x 7
14 u - 588 = 21 p --- (4)
(4) = (3)
14 u - 588 = 9 u - 78
14 u - 9 u = 588 - 78
5 u = 510
1 u = 510 ÷ 5 = 102
Number of stickers that Adam has now
= 3 u - 26 + 2 u - 84
= 5 u - 110
= 5 x 102 - 110
= 510 - 110
= 400
Answer(s): 400