Adam has 75 stickers.
After
47 of the blue stickers is given away and
another 5 green stickers are bought,
there is an equal number of blue and green stickers.
- How many blue stickers are there in the end?
- How many less green stickers than blue stickers are there at first?
- How many blue stickers are given away?
|
Blue |
Green |
Before |
7 u |
3 u - 5 |
Change |
- 4 u |
+ 5 |
After |
3 u |
3 u |
(a)
Fraction of the blue stickers left
= 1 -
47 =
37 The number of blue stickers and green stickers in the end is the same.
Total number of stickers at first
= 7 u + 3 u - 5
= 10 u - 5
10 u - 5 = 75
10 u = 75 + 5
10 u = 80
1 u = 80 ÷ 10 = 8
Number of blue stickers in the end
= 3 u
= 3 x 8
= 24
(b)
Number of less green stickers than blue stickers at first
= 7 u - (3 u - 5)
= 7 u - 3 u + 5
= 4 u + 5
= 4 x 8 + 5
= 32 + 5
= 37
(c)
Number of blue stickers given away
= 4 u
= 4 x 8
= 32
Answer(s): (a) 24; (b) 37; (c) 32