Adam has some red stickers and blue stickers.
If 149 red stickers are added, 40% of the stickers will be blue stickers.
If 176 blue stickers are added, 25% of the stickers will be red stickers.
- How many red stickers are there?
- How many blue stickers are there?
|
Scenario 1 |
Scenario 2 |
|
Red |
Blue |
Red |
Blue |
Before |
3 u - 149 |
2 u |
1 p |
3 p - 176 |
Change |
+ 149 |
No change |
No change |
+ 176 |
After |
3 u |
2 u |
1 p |
3 p |
(a)
40% =
40100 =
25 25% =
25100 =
14 Scenario 1 Fraction of the stickers that are red
= 1 -
25 =
35 Number of red stickers at first = 3 u - 149
Number of blue stickers at first = 2 u
Scenario 2 Fraction of the stickers that are blue
= 1 -
14=
34 Number of red stickers at first = 1 p
Number of blue stickers at first = 3 p - 176
3 u - 149 = 1 p --- (1)
2 u = 3 p - 176
2 u + 176 = 3 p --- (2)
(1)
x 3 9 u - 447 = 3 p --- (3)
(3) = (2)
9 u - 447 = 2 u + 176
9 u - 2 u = 447 + 176
7 u = 623
1 u = 623 ÷ 7 = 89
Number of red stickers
= 3 u - 149
= 3 x 89 - 149
= 267 - 149
= 118
(b)
Number of blue stickers
= 2 u
= 2 x 89
= 178
Answer(s): (a) 118; (b) 178