Adam has some red stickers and blue stickers.
If 372 red stickers are added, 40% of the stickers will be blue stickers.
If 179 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 - 372 |
2 u |
1 p |
3 p - 179 |
Change |
+ 372 |
No change |
No change |
+ 179 |
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 - 372
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 - 179
3 u - 372 = 1 p --- (1)
2 u = 3 p - 179
2 u + 179 = 3 p --- (2)
(1)
x 3 9 u - 1116 = 3 p --- (3)
(3) = (2)
9 u - 1116 = 2 u + 179
9 u - 2 u = 1116 + 179
7 u = 1295
1 u = 1295 ÷ 7 = 185
Number of red stickers
= 3 u - 372
= 3 x 185 - 372
= 555 - 372
= 183
(b)
Number of blue stickers
= 2 u
= 2 x 185
= 370
Answer(s): (a) 183; (b) 370