Adam has some red stickers and green stickers.
If 276 red stickers are added, 40% of the stickers will be green stickers.
If 299 green stickers are added, 25% 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 - 276 |
2 u |
1 p |
3 p - 299 |
Change |
+ 276 |
No change |
No change |
+ 299 |
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 - 276
Number of green stickers at first = 2 u
Scenario 2 Fraction of the stickers that are green
= 1 -
14=
34 Number of red stickers at first = 1 p
Number of green stickers at first = 3 p - 299
3 u - 276 = 1 p --- (1)
2 u = 3 p - 299
2 u + 299 = 3 p --- (2)
(1)
x 3 9 u - 828 = 3 p --- (3)
(3) = (2)
9 u - 828 = 2 u + 299
9 u - 2 u = 828 + 299
7 u = 1127
1 u = 1127 ÷ 7 = 161
Number of red stickers
= 3 u - 276
= 3 x 161 - 276
= 483 - 276
= 207
(b)
Number of green stickers
= 2 u
= 2 x 161
= 322
Answer(s): (a) 207; (b) 322