Adam has 600 green and red stickers.
He sells 90 green stickers and the number of red stickers becomes 2 times as many as green stickers.
- How many more red stickers than green stickers does Adam have at first?
- How many less green stickers than red stickers does Adam have in the end?
|
Green |
Red |
Before |
1 u + 90 |
2 u |
Change |
- 90 |
No Change |
After |
1 u |
2 u |
(a)
The number of red stickers remains unchanged.
Total number of stickers at first
= 1 u + 90 + 2 u
= 3 u + 90
3 u + 90 = 600
3 u = 600 - 90
3 u = 510
1 u = 510 ÷ 3 = 170
Number of more red stickers than green stickers at first
= 2 u - (1 u + 90)
= 2 u - 1 u - 90
= 1 u - 90
= 1 x 170 - 90
= 170 - 90
= 80
(b)
Number of less green stickers than red stickers in the end
= 2 u - 1 u
= 1 u
= 1 x 170
= 170
Answer(s): (a) 80; (b) 170