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 30% to 98.
- How many stickers are there at first?
- How many stickers are there in the end?
|
Blue |
Green |
Before |
100% |
100% |
Change |
+ 20% |
- 30% |
After |
120% = 90 |
70% = 98 |
(a)
100% - 20% = 120%
120% of blue stickers = 90
100% of blue stickers =
90120 x 100 = 75
100% - 30% = 70%
70% of green stickers = 98
100% of green stickers =
9870 x 100 = 140
Number of stickers at first
= 100% of blue stickers + 100% of green stickers
= 75 + 140
= 215
(b)
Number of stickers in the end
= 90 + 98
= 188
Answer(s): (a) 215; (b) 188