Adam has 197 stickers.
After
57 of the red stickers is given away and
another 37 blue stickers are bought,
there is an equal number of red and blue stickers.
- How many red stickers are there in the end?
- How many less blue stickers than red stickers are there at first?
- How many red stickers are given away?
|
Red |
Blue |
Before |
7 u |
2 u - 37 |
Change |
- 5 u |
+ 37 |
After |
2 u |
2 u |
(a)
Fraction of the red stickers left
= 1 -
57 =
27 The number of red stickers and blue stickers in the end is the same.
Total number of stickers at first
= 7 u + 2 u - 37
= 9 u - 37
9 u - 37 = 197
9 u = 197 + 37
9 u = 234
1 u = 234 ÷ 9 = 26
Number of red stickers in the end
= 2 u
= 2 x 26
= 52
(b)
Number of less blue stickers than red stickers at first
= 7 u - (2 u - 37)
= 7 u - 2 u + 37
= 5 u + 37
= 5 x 26 + 37
= 130 + 37
= 167
(c)
Number of red stickers given away
= 5 u
= 5 x 26
= 130
Answer(s): (a) 52; (b) 167; (c) 130