Adam has 138 stickers.
After
58 of the red stickers is given away and
another 27 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 |
8 u |
3 u - 27 |
Change |
- 5 u |
+ 27 |
After |
3 u |
3 u |
(a)
Fraction of the red stickers left
= 1 -
58 =
38 The number of red stickers and blue stickers in the end is the same.
Total number of stickers at first
= 8 u + 3 u - 27
= 11 u - 27
11 u - 27 = 138
11 u = 138 + 27
11 u = 165
1 u = 165 ÷ 11 = 15
Number of red stickers in the end
= 3 u
= 3 x 15
= 45
(b)
Number of less blue stickers than red stickers at first
= 8 u - (3 u - 27)
= 8 u - 3 u + 27
= 5 u + 27
= 5 x 15 + 27
= 75 + 27
= 102
(c)
Number of red stickers given away
= 5 u
= 5 x 15
= 75
Answer(s): (a) 45; (b) 102; (c) 75