Adam has 75 blue stickers.
He has 5 times as many blue stickers as red stickers.
After he buys an equal number of blue and red stickers,
the number of blue stickers is 4 times that of the red stickers.
- How many blue stickers are there in the end?
- How many red stickers are there in the end?
- How many stickers are there in the end?
- How many stickers does Adam buy?
|
Blue stickers |
Red stickers |
Difference |
Before |
5 x 3 = 15 u |
1 x 3 = 3 u |
4 x 3 = 12 u |
Change |
+ ? |
+ ? |
|
After |
4 x 4 = 16 u |
1 x 4 = 4 u |
3 x 4 = 12 u |
(a)
The difference in the number between the blue and red stickers at first and in the end remains unchanged.
LCM of 4 and 3 is 12.
15 u = 75
1 u = 75 ÷ 15 = 5
Number of blue stickers in the end
= 16 u
= 16 x 5
= 80
(b)
Number of red stickers in the end
= 4 u
= 4 x 5
= 20
(c)
Total number of stickers in the end
= 80 + 20
= 100
(d)
Total number of stickers that Adam buys
= (16 u - 15 u) x 2
= 1 u x 2
= 2 u
= 2 x 5
= 10
Answer(s): (a) 80; (b) 20; (c) 100; (d) 10