Adam has 192 stickers.
After
37 of the red stickers is given away and
another 39 green stickers are bought,
there is an equal number of red and green stickers.
- How many red stickers are there in the end?
- How many less green stickers than red stickers are there at first?
- How many red stickers are given away?
|
Red |
Green |
Before |
7 u |
4 u - 39 |
Change |
- 3 u |
+ 39 |
After |
4 u |
4 u |
(a)
Fraction of the red stickers left
= 1 -
37 =
47 The number of red stickers and green stickers in the end is the same.
Total number of stickers at first
= 7 u + 4 u - 39
= 11 u - 39
11 u - 39 = 192
11 u = 192 + 39
11 u = 231
1 u = 231 ÷ 11 = 21
Number of red stickers in the end
= 4 u
= 4 x 21
= 84
(b)
Number of less green stickers than red stickers at first
= 7 u - (4 u - 39)
= 7 u - 4 u + 39
= 3 u + 39
= 3 x 21 + 39
= 63 + 39
= 102
(c)
Number of red stickers given away
= 3 u
= 3 x 21
= 63
Answer(s): (a) 84; (b) 102; (c) 63