Adam has 191 stickers.
After
27 of the red stickers is given away and
another 13 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 |
5 u - 13 |
Change |
- 2 u |
+ 13 |
After |
5 u |
5 u |
(a)
Fraction of the red stickers left
= 1 -
27 =
57 The number of red stickers and green stickers in the end is the same.
Total number of stickers at first
= 7 u + 5 u - 13
= 12 u - 13
12 u - 13 = 191
12 u = 191 + 13
12 u = 204
1 u = 204 ÷ 12 = 17
Number of red stickers in the end
= 5 u
= 5 x 17
= 85
(b)
Number of less green stickers than red stickers at first
= 7 u - (5 u - 13)
= 7 u - 5 u + 13
= 2 u + 13
= 2 x 17 + 13
= 34 + 13
= 47
(c)
Number of red stickers given away
= 2 u
= 2 x 17
= 34
Answer(s): (a) 85; (b) 47; (c) 34