Adam has some blue stickers and red stickers.
The number of blue stickers is decreased by 20% to 72.
The number of red stickers is decreased by 40% to 84.
- How many stickers are there at first?
- How many stickers are there in the end?
|
Blue |
Red |
Before |
100% |
100% |
Change |
- 20% |
- 40% |
After |
80% = 72 |
60% = 84 |
(a)
100% - 20% = 80%
80% of blue stickers = 72
100% of blue stickers =
7280 x 100 = 90
100% - 40% = 60%
60% of red stickers = 84
100% of red stickers =
8460 x 100 = 140
Number of stickers at first
= 100% of blue stickers + 100% of red stickers
= 90 + 140
= 230
(b)
Number of stickers in the end
= 72 + 84
= 156
Answer(s): (a) 230; (b) 156