Adam has 44 stickers.
After
310 of the green stickers is given away and
another 7 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 |
10 u |
7 u - 7 |
Change |
- 3 u |
+ 7 |
After |
7 u |
7 u |
(a)
Fraction of the green stickers left
= 1 -
310 =
710 The number of green stickers and red stickers in the end is the same.
Total number of stickers at first
= 10 u + 7 u - 7
= 17 u - 7
17 u - 7 = 44
17 u = 44 + 7
17 u = 51
1 u = 51 ÷ 17 = 3
Number of green stickers in the end
= 7 u
= 7 x 3
= 21
(b)
Number of less red stickers than green stickers at first
= 10 u - (7 u - 7)
= 10 u - 7 u + 7
= 3 u + 7
= 3 x 3 + 7
= 9 + 7
= 16
(c)
Number of green stickers given away
= 3 u
= 3 x 3
= 9
Answer(s): (a) 21; (b) 16; (c) 9