Answer: 60 dollars
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Work Shown:
x = original price
y = sale price
The sale price is always smaller than the original price, so y < x.
The equation linking the two variables is
y = 0.8x
since 80% = 80/100 = 0.8
We know the sale price is $48, which means y = 48. This leads to:
y = 0.8x
0.8x = y
0.8x = 48
x = 48/0.8
x = 60
The original price was $60
Note: since the sale price is 80% of the original price, this must mean that we have a 20% discount (100% - 80% = 20%)