Answer:
$51.20 is the cost after a 20% reduction.
Step-by-step explanation:
There are two ways that this can be determined.
First, we can find what 20% of the original $64 price is and subtract the discount from the price.
20% = 0.20
0.20 ( $64) = $12.80
$64 - $12.80 = $51.20
Or
We can say that $64 is 100% of the price and subtract the 20% meaning the sale price will be 80% of the original price.
100% = 1.00 20% = .20
$64(1.00-.20) = $64(.80) = $51.20