The ratio of the number of red stickers to blue stickers is 5 : 3.
After Adam gives away 90 red stickers and gives away 88 blue stickers,
the ratio becomes of the number of red stickers to blue stickers is 9 : 2.
How many stickers does Adam have now?
|
Make p the same (1) x 2 = (3) |
(1) Red |
(2) Blue |
Make p the same (2) x 9 = (4) |
Before |
10 u |
5 u |
3 u |
27 u |
Change |
- 180 |
- 90 |
- 88 |
- 792 |
After |
18 p |
9 p |
2 p |
18 p |
5 u - 90 = 9 p --- (1)
3 u - 88 = 2 p --- (2)
Make p the same.
(1) x 2
10 u - 180 = 18 p --- (3)
(2) x 9
27 u - 792 = 18 p --- (4)
(4) = (3)
27 u - 792 = 10 u - 180
27 u - 10 u = 792 - 180
17 u = 612
1 u = 612 ÷ 17 = 36
Number of stickers that Adam has now
= 5 u - 90 + 3 u - 88
= 8 u - 178
= 8 x 36 - 178
= 288 - 178
= 110
Answer(s): 110