Adam has 500 stickers.
After
18 of the red stickers and
20 blue stickers are given away,
there is an equal number of red and blue stickers left.
- How many red stickers are there in the end?
- How many more red stickers than blue stickers are there at first?
- How many red stickers are given away?
|
Red stickers |
Blue stickers |
Total |
Before |
8 u |
7 u + 20 |
500 |
Change |
- 1 u |
- 20 |
|
After |
7 u |
7 u |
|
(a)
Fraction of the red stickers left
= 1 -
18 =
78 Total number of stickers at first
= 8 u + 7 u + 20
= 15 u + 20
15 u + 20 = 500
15 u = 500 - 20
15 u = 480
1 u = 480 ÷ 15 = 32
Number of red stickers in the end
= 7 u
= 7 x 32
= 224
(b)
Number of more red stickers than blue stickers at first
= 8 u - (7 u + 20)
= 8 u - 7 u - 20
= 1 u - 20
= 1 x 32 - 20
= 32 - 20
= 12
(c)
Number of red stickers given away
= 1 u
= 32
Answer(s): (a) 224; (b) 12; (c) 32