Adam has 500 blue and green stickers.
He buys 70 blue stickers and the number of blue stickers becomes 2 times as many as green stickers.
- How many more blue stickers than green stickers does Adam have at first?
- How many less green stickers than blue stickers does Adam have in the end?
|
Blue |
Green |
Before |
2 u - 70 |
1 u |
Change |
+ 70 |
No change |
After |
2 u |
1 u |
(a)
The number of green stickers remain unchanged.
Total number of stickers at first
= 1 u + 2 u - 70
= 3 u - 70
3 u - 70 = 500
3 u = 500 + 70
3 u = 570
1 u = 570 ÷ 3 = 190
Number of more blue stickers than green stickers at first
= (2 u - 70) - 1 u
= 2 u - 1 u - 70
= 1 u - 70
= 1 x 190 - 70
= 190 - 70
= 120
(b)
Number of less green stickers than blue stickers in the end
= 2 u - 1 u
= 1 u
= 1 x 190
= 190
Answer(s): (a) 120; (b) 190