Adam has some blue stickers and red stickers.
The number of blue stickers is decreased by 40% to 90.
The number of red stickers is decreased by 10% to 72.
- How many stickers are there at first?
- How many stickers are there in the end?
|
Red |
Green |
Before |
100% |
100% |
Change |
- 40% |
- 10% |
After |
60% = 90 |
90% = 72 |
(a)
100% - 40% = 60%
60% of red stickers = 90
100% of red stickers =
9060 x 100 = 150
100% - 10% = 90%
90% of green stickers = 72
100% of green stickers =
7290 x 100 = 80
Number of stickers at first
= 100% of red stickers + 100% of green stickers
= 150 + 80
= 230
(b)
Number of stickers in the end
= 90 + 72
= 162
Answer(s): (a) 230; (b) 162