Adam has 83 stickers.
After
47 of the green stickers is given away and
another 17 red stickers are bought,
there is an equal number of green and red stickers.
- How many green stickers are there in the end?
- How many less red stickers than green stickers are there at first?
- How many green stickers are given away?
|
Green |
Red |
Before |
7 u |
3 u - 17 |
Change |
- 4 u |
+ 17 |
After |
3 u |
3 u |
(a)
Fraction of the green stickers left
= 1 -
47 =
37 The number of green stickers and red stickers in the end is the same.
Total number of stickers at first
= 7 u + 3 u - 17
= 10 u - 17
10 u - 17 = 83
10 u = 83 + 17
10 u = 100
1 u = 100 ÷ 10 = 10
Number of green stickers in the end
= 3 u
= 3 x 10
= 30
(b)
Number of less red stickers than green stickers at first
= 7 u - (3 u - 17)
= 7 u - 3 u + 17
= 4 u + 17
= 4 x 10 + 17
= 40 + 17
= 57
(c)
Number of green stickers given away
= 4 u
= 4 x 10
= 40
Answer(s): (a) 30; (b) 57; (c) 40