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