Adam has 900 red and green stickers.
He buys 70 red stickers and the number of red stickers becomes 4 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?
|
Red |
Green |
Before |
4 u - 70 |
1 u |
Change |
+ 70 |
No change |
After |
4 u |
1 u |
(a)
The number of green stickers remain unchanged.
Total number of stickers at first
= 1 u + 4 u - 70
= 5 u - 70
5 u - 70 = 900
5 u = 900 + 70
5 u = 970
1 u = 970 ÷ 5 = 194
Number of more red stickers than green stickers at first
= (4 u - 70) - 1 u
= 4 u - 1 u - 70
= 3 u - 70
= 3 x 194 - 70
= 582 - 70
= 512
(b)
Number of less green stickers than red stickers in the end
= 4 u - 1 u
= 3 u
= 3 x 194
= 582
Answer(s): (a) 512; (b) 582