Adam has some blue stickers and red stickers.
The number of blue stickers is increased by 20% to 72.
The number of red stickers is decreased by 50% to 81.
- How many stickers are there at first?
- How many stickers are there in the end?
|
Red |
Green |
Before |
100% |
100% |
Change |
+ 20% |
- 50% |
After |
120% = 72 |
50% = 81 |
(a)
100% - 20% = 120%
120% of red stickers = 72
100% of red stickers =
72120 x 100 = 60
100% - 50% = 50%
50% of green stickers = 81
100% of green stickers =
8150 x 100 = 162
Number of stickers at first
= 100% of red stickers + 100% of green stickers
= 60 + 162
= 222
(b)
Number of stickers in the end
= 72 + 81
= 153
Answer(s): (a) 222; (b) 153