Adam has some red stickers and green stickers.
If 311 red stickers are removed, 80% of the stickers will be green stickers.
If 39 red stickers are added, 30% of the stickers will be green stickers.
- How many red stickers are there?
- How many green stickers are there?
|
Scenario 1 |
Scenario 2 |
|
Red |
Green |
Red |
Green |
Before |
3 u + 311 |
12 u |
28 u - 39 |
12 u |
Change |
- 311 |
No change |
+ 39 |
No change |
After |
1x3 = 3 u |
4x3 = 12 u |
7x4 = 28 u |
3x4 = 12 u |
(a)
80% =
80100 =
4530% =
30100 =
310Scenario 1 Fraction of the stickers that are red in the end
= 1 -
45 =
15 Scenario 2
Fraction of the stickers that are red in the end
= 1 -
310 =
710 The number of green stickers remains unchanged in both scenarios.
LCM of 4 and 3 = 12
28 u - 39 = 3 u + 311
28 u - 3 u = 311 + 39
25 u = 350
1 u = 350 ÷ 25 = 14
Number of red stickers
= 3 u + 311
= 3 x 14 + 311
= 42 + 311
= 353
(b)
Number of green stickers
= 12 u
= 12 x 14
= 168
Answer(s): (a) 353; (b) 168