Adam has 175 stickers.
After
25 of the red stickers is given away and
another 9 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 |
5 u |
3 u - 9 |
Change |
- 2 u |
+ 9 |
After |
3 u |
3 u |
(a)
Fraction of the red stickers left
= 1 -
25 =
35 The number of red stickers and blue stickers in the end is the same.
Total number of stickers at first
= 5 u + 3 u - 9
= 8 u - 9
8 u - 9 = 175
8 u = 175 + 9
8 u = 184
1 u = 184 ÷ 8 = 23
Number of red stickers in the end
= 3 u
= 3 x 23
= 69
(b)
Number of less blue stickers than red stickers at first
= 5 u - (3 u - 9)
= 5 u - 3 u + 9
= 2 u + 9
= 2 x 23 + 9
= 46 + 9
= 55
(c)
Number of red stickers given away
= 2 u
= 2 x 23
= 46
Answer(s): (a) 69; (b) 55; (c) 46