Emily baked 50 puffs. 40% of them were vanila puffs. How many more vanila puffs must Emily bake so that 85% of her puffs are vanila puffs?
| |
Vanila puffs |
Other puffs |
| Before |
40% |
60% |
| Change |
+ ? |
No change |
| After |
85 u |
15 u |
Number of vanila puffs at first
= 40% x 50
=
40100 x 50
= 20
Percentage of other puffs
= 100% - 40%
= 60%
Number of other puffs
= 60% x 50
=
60100 x 50
= 30
Number of other puffs in the end
= 100 u - 85 u
= 15 u
The number of other puffs remains unchanged.
60% = 15 u
15 u = 30
1 u = 30 ÷ 15 = 2
Number of vanila puffs in the end
= 85 u
= 85 x 2
= 170
Additional number of vanila puffs that Emily must bake
= 170 - 20
= 150
Answer(s): 150
