Adam has 300 red and blue stickers.
He buys 30 red stickers and the number of red stickers becomes 5 times as many as blue stickers.
- How many more red stickers than blue stickers does Adam have at first?
- How many less blue stickers than red stickers does Adam have in the end?
|
Red |
Blue |
Before |
5 u - 30 |
1 u |
Change |
+ 30 |
No change |
After |
5 u |
1 u |
(a)
The number of blue stickers remain unchanged.
Total number of stickers at first
= 1 u + 5 u - 30
= 6 u - 30
6 u - 30 = 300
6 u = 300 + 30
6 u = 330
1 u = 330 ÷ 6 = 55
Number of more red stickers than blue stickers at first
= (5 u - 30) - 1 u
= 5 u - 1 u - 30
= 4 u - 30
= 4 x 55 - 30
= 220 - 30
= 190
(b)
Number of less blue stickers than red stickers in the end
= 5 u - 1 u
= 4 u
= 4 x 55
= 220
Answer(s): (a) 190; (b) 220