Adam has some blue stickers and red stickers.
The number of blue stickers is increased by 20% to 90.
The number of red stickers is decreased by 50% to 82.
- How many stickers are there at first?
- How many stickers are there in the end?
|
Green |
Red |
Before |
100% |
100% |
Change |
+ 20% |
- 50% |
After |
120% = 90 |
50% = 82 |
(a)
100% - 20% = 120%
120% of green stickers = 90
100% of green stickers =
90120 x 100 = 75
100% - 50% = 50%
50% of red stickers = 82
100% of red stickers =
8250 x 100 = 164
Number of stickers at first
= 100% of green stickers + 100% of red stickers
= 75 + 164
= 239
(b)
Number of stickers in the end
= 90 + 82
= 172
Answer(s): (a) 239; (b) 172