Adam has some red stickers and green stickers.
If 174 red stickers are added, 40% of the stickers will be green stickers.
If 284 green stickers are added, 20% of the stickers will be red stickers.
- How many red stickers are there?
- How many green stickers are there?
|
Scenario 1 |
Scenario 2 |
|
Red |
Green |
Red |
Green |
Before |
3 u - 174 |
2 u |
1 p |
4 p - 284 |
Change |
+ 174 |
No change |
No change |
+ 284 |
After |
3 u |
2 u |
1 p |
4 p |
(a)
40% =
40100 =
25 20% =
20100 =
15 Scenario 1 Fraction of the stickers that are red
= 1 -
25 =
35 Number of red stickers at first = 3 u - 174
Number of green stickers at first = 2 u
Scenario 2 Fraction of the stickers that are green
= 1 -
15=
45 Number of red stickers at first = 1 p
Number of green stickers at first = 4 p - 284
3 u - 174 = 1 p --- (1)
2 u = 4 p - 284
2 u + 284 = 4 p --- (2)
(1)
x 4 12 u - 696 = 4 p --- (3)
(3) = (2)
12 u - 696 = 2 u + 284
12 u - 2 u = 696 + 284
10 u = 980
1 u = 980 ÷ 10 = 98
Number of red stickers
= 3 u - 174
= 3 x 98 - 174
= 294 - 174
= 120
(b)
Number of green stickers
= 2 u
= 2 x 98
= 196
Answer(s): (a) 120; (b) 196