Adam has some blue stickers and red stickers.
If Adam receives another 800 red stickers,
the blue stickers will be 20% as many as the red stickers.
If Adam receives another 23 blue stickers,
the blue stickers will be 80% as many as the red stickers.
- How many blue stickers are there?
- How many red stickers are there?
|
Scenario 1 |
Scenario 2 |
|
Blue |
Red |
Blue |
Red |
Before |
1 u |
5 u - 800 |
4 p - 23 |
5 p |
Change |
No change |
+ 800 |
+ 23 |
No change |
After |
1 u |
5 u |
4 p |
5 p |
(a)
20% =
20100 =
15 80% =
80100 =
45 Scenario 1 Number of blue stickers at first = 1 u
Number of red stickers at first = 5 u - 800
Scenario 2 Number of blue stickers at first = 4 p - 23
Number of red stickers at first = 5 p
1 u = 4 p - 23 --- (1)
5 u - 800 = 5 p --- (2)
(2)
÷ 51 u - 160 = 1 p
1 u = 1 p + 160 --- (3)
(1) = (3)
4 p - 23 = 1 p + 160
4 p - 1 p = 23 + 160
3 p = 183
1 p = 183 ÷ 3 = 61
Number of blue stickers
= 4 p - 23
= 4 x 61 - 23
= 244 - 23
= 221
(b)
Number of red stickers
= 5 p
= 5 x 61
= 305
Answer(s): (a) 221; (b) 305