Adam has 60 red stickers.
He has 3 times as many red stickers as blue stickers.
After he buys an equal number of red and blue stickers,
the number of red stickers is 2 times that of the blue stickers.
- How many red stickers are there in the end?
- How many blue stickers are there in the end?
- How many stickers are there in the end?
- How many stickers does Adam buy?
|
Red stickers |
Blue stickers |
Difference |
Before |
3 x 1 = 3 u |
1 x 1 = 1 u |
2 x 1 = 2 u |
Change |
+ ? |
+ ? |
|
After |
2 x 2 = 4 u |
1 x 2 = 2 u |
1 x 2 = 2 u |
(a)
The difference in the number between the red and blue stickers at first and in the end remains unchanged.
LCM of 2 and 1 is 2.
3 u = 60
1 u = 60 ÷ 3 = 20
Number of red stickers in the end
= 4 u
= 4 x 20
= 80
(b)
Number of blue stickers in the end
= 2 u
= 2 x 20
= 40
(c)
Total number of stickers in the end
= 80 + 40
= 120
(d)
Total number of stickers that Adam buys
= (4 u - 3 u) x 2
= 1 u x 2
= 2 u
= 2 x 20
= 40
Answer(s): (a) 80; (b) 40; (c) 120; (d) 40