Adam has 162 stickers.
After
25 of the green stickers is given away and
another 30 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 |
5 u |
3 u - 30 |
Change |
- 2 u |
+ 30 |
After |
3 u |
3 u |
(a)
Fraction of the green stickers left
= 1 -
25 =
35 The number of green stickers and red stickers in the end is the same.
Total number of stickers at first
= 5 u + 3 u - 30
= 8 u - 30
8 u - 30 = 162
8 u = 162 + 30
8 u = 192
1 u = 192 ÷ 8 = 24
Number of green stickers in the end
= 3 u
= 3 x 24
= 72
(b)
Number of less red stickers than green stickers at first
= 5 u - (3 u - 30)
= 5 u - 3 u + 30
= 2 u + 30
= 2 x 24 + 30
= 48 + 30
= 78
(c)
Number of green stickers given away
= 2 u
= 2 x 24
= 48
Answer(s): (a) 72; (b) 78; (c) 48