The ratio of the number of red stickers to green stickers is 4 : 3.
After Adam gives away 38 red stickers and gives away 23 green stickers,
the ratio becomes of the number of red stickers to green stickers is 9 : 4.
How many stickers does Adam have now?
|
Make p the same (1) x 4 = (3) |
(1) Red |
(2) Green |
Make p the same (2) x 9 = (4) |
Before |
16 u |
4 u |
3 u |
27 u |
Change |
- 152 |
- 38 |
- 23 |
- 207 |
After |
36 p |
9 p |
4 p |
36 p |
4 u - 38 = 9 p --- (1)
3 u - 23 = 4 p --- (2)
Make p the same.
(1) x 4
16 u - 152 = 36 p --- (3)
(2) x 9
27 u - 207 = 36 p --- (4)
(4) = (3)
27 u - 207 = 16 u - 152
27 u - 16 u = 207 - 152
11 u = 55
1 u = 55 ÷ 11 = 5
Number of stickers that Adam has now
= 4 u - 38 + 3 u - 23
= 7 u - 61
= 7 x 5 - 61
= 35 - 61
= -26
Answer(s): -26