Adam has 400 blue and red stickers.
He buys 60 blue stickers and the number of blue stickers becomes 3 times as many as red stickers.
- How many more blue stickers than red stickers does Adam have at first?
- How many less red stickers than blue stickers does Adam have in the end?
|
Blue |
Red |
Before |
3 u - 60 |
1 u |
Change |
+ 60 |
No change |
After |
3 u |
1 u |
(a)
The number of red stickers remain unchanged.
Total number of stickers at first
= 1 u + 3 u - 60
= 4 u - 60
4 u - 60 = 400
4 u = 400 + 60
4 u = 460
1 u = 460 ÷ 4 = 115
Number of more blue stickers than red stickers at first
= (3 u - 60) - 1 u
= 3 u - 1 u - 60
= 2 u - 60
= 2 x 115 - 60
= 230 - 60
= 170
(b)
Number of less red stickers than blue stickers in the end
= 3 u - 1 u
= 2 u
= 2 x 115
= 230
Answer(s): (a) 170; (b) 230