Adam has 152 stickers.
After
47 of the blue stickers is given away and
another 48 red stickers are bought,
there is an equal number of blue and red stickers.
- How many blue stickers are there in the end?
- How many less red stickers than blue stickers are there at first?
- How many blue stickers are given away?
|
Blue |
Red |
Before |
7 u |
3 u - 48 |
Change |
- 4 u |
+ 48 |
After |
3 u |
3 u |
(a)
Fraction of the blue stickers left
= 1 -
47 =
37 The number of blue stickers and red stickers in the end is the same.
Total number of stickers at first
= 7 u + 3 u - 48
= 10 u - 48
10 u - 48 = 152
10 u = 152 + 48
10 u = 200
1 u = 200 ÷ 10 = 20
Number of blue stickers in the end
= 3 u
= 3 x 20
= 60
(b)
Number of less red stickers than blue stickers at first
= 7 u - (3 u - 48)
= 7 u - 3 u + 48
= 4 u + 48
= 4 x 20 + 48
= 80 + 48
= 128
(c)
Number of blue stickers given away
= 4 u
= 4 x 20
= 80
Answer(s): (a) 60; (b) 128; (c) 80