The ratio of the number of blue stickers to red stickers is 3 : 2.
After Adam gives away 57 blue stickers and gives away 70 red stickers,
the ratio becomes of the number of blue stickers to red stickers is 9 : 2.
How many stickers does Adam have now?
|
Make p the same (1) x 2 = (3) |
(1) Blue |
(2) Red |
Make p the same (2) x 9 = (4) |
Before |
6 u |
3 u |
2 u |
18 u |
Change |
- 114 |
- 57 |
- 70 |
- 630 |
After |
18 p |
9 p |
2 p |
18 p |
3 u - 57 = 9 p --- (1)
2 u - 70 = 2 p --- (2)
Make p the same.
(1) x 2
6 u - 114 = 18 p --- (3)
(2) x 9
18 u - 630 = 18 p --- (4)
(4) = (3)
18 u - 630 = 6 u - 114
18 u - 6 u = 630 - 114
12 u = 516
1 u = 516 ÷ 12 = 43
Number of stickers that Adam has now
= 3 u - 57 + 2 u - 70
= 5 u - 127
= 5 x 43 - 127
= 215 - 127
= 88
Answer(s): 88