Adam has some green stickers and red stickers.
If 276 green stickers are added, 40% of the stickers will be red stickers.
If 196 red stickers are added, 20% of the stickers will be green stickers.
- How many green stickers are there?
- How many red stickers are there?
|
Scenario 1 |
Scenario 2 |
|
Green |
Red |
Green |
Red |
Before |
3 u - 276 |
2 u |
1 p |
4 p - 196 |
Change |
+ 276 |
No change |
No change |
+ 196 |
After |
3 u |
2 u |
1 p |
4 p |
(a)
40% =
40100 =
25 20% =
20100 =
15 Scenario 1 Fraction of the stickers that are green
= 1 -
25 =
35 Number of green stickers at first = 3 u - 276
Number of red stickers at first = 2 u
Scenario 2 Fraction of the stickers that are red
= 1 -
15=
45 Number of green stickers at first = 1 p
Number of red stickers at first = 4 p - 196
3 u - 276 = 1 p --- (1)
2 u = 4 p - 196
2 u + 196 = 4 p --- (2)
(1)
x 4 12 u - 1104 = 4 p --- (3)
(3) = (2)
12 u - 1104 = 2 u + 196
12 u - 2 u = 1104 + 196
10 u = 1300
1 u = 1300 ÷ 10 = 130
Number of green stickers
= 3 u - 276
= 3 x 130 - 276
= 390 - 276
= 114
(b)
Number of red stickers
= 2 u
= 2 x 130
= 260
Answer(s): (a) 114; (b) 260