Adam has 60 stickers.
After
37 of the green stickers is given away and
another 17 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 |
7 u |
4 u - 17 |
Change |
- 3 u |
+ 17 |
After |
4 u |
4 u |
(a)
Fraction of the green stickers left
= 1 -
37 =
47 The number of green stickers and blue stickers in the end is the same.
Total number of stickers at first
= 7 u + 4 u - 17
= 11 u - 17
11 u - 17 = 60
11 u = 60 + 17
11 u = 77
1 u = 77 ÷ 11 = 7
Number of green stickers in the end
= 4 u
= 4 x 7
= 28
(b)
Number of less blue stickers than green stickers at first
= 7 u - (4 u - 17)
= 7 u - 4 u + 17
= 3 u + 17
= 3 x 7 + 17
= 21 + 17
= 38
(c)
Number of green stickers given away
= 3 u
= 3 x 7
= 21
Answer(s): (a) 28; (b) 38; (c) 21