Adam has 72 stickers.
After
49 of the green stickers is given away and
another 12 blue stickers are bought,
there is an equal number of green and blue stickers.
- How many green stickers are there in the end?
- How many less blue stickers than green stickers are there at first?
- How many green stickers are given away?
|
Green |
Blue |
Before |
9 u |
5 u - 12 |
Change |
- 4 u |
+ 12 |
After |
5 u |
5 u |
(a)
Fraction of the green stickers left
= 1 -
49 =
59 The number of green stickers and blue stickers in the end is the same.
Total number of stickers at first
= 9 u + 5 u - 12
= 14 u - 12
14 u - 12 = 72
14 u = 72 + 12
14 u = 84
1 u = 84 ÷ 14 = 6
Number of green stickers in the end
= 5 u
= 5 x 6
= 30
(b)
Number of less blue stickers than green stickers at first
= 9 u - (5 u - 12)
= 9 u - 5 u + 12
= 4 u + 12
= 4 x 6 + 12
= 24 + 12
= 36
(c)
Number of green stickers given away
= 4 u
= 4 x 6
= 24
Answer(s): (a) 30; (b) 36; (c) 24