The ratio of the number of red stickers to blue stickers is 8 : 1.
After Adam buys another 35 blue stickers and gives away 17 red stickers,
the ratio becomes of the number of red stickers to blue stickers is 5 : 4.
How many stickers does Adam have now?
|
Make p the same (1) x 4 = (3) |
(1) Red |
(2) Blue |
Make p the same (2) x 5 = (4) |
Before |
32 u |
8 u |
1 u |
5 u |
Change |
- 68 |
- 17 |
+ 35 |
+ 175 |
After |
20 p |
5 p |
4 p |
20 p |
8 u + 35 = 5 p --- (1)
1 u - 17 = 4 p --- (2)
Make p the same.
(1)
x 432 u - 68 = 20 p --- (3)
(2)
x 55 u + 175 = 20 p --- (4)
(3) = (4)
32 u - 68 = 5 u + 175
32 u - 5 u = 68 + 175
27 u = 243
1 u = 243 ÷ 27 = 9
Number of stickers that Adam have now
= 8 u + 35 + 1 u - 17
= 8 u + 1 u + 35 - 17
= 9 u + 18
= 9 x 9 + 18
= 81 + 18
= 99
Answer(s): 99