Answer: $200
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Work Shown:
If you save 64%, then you still have to pay the remaining 100% - 64% = 36%
x = original price in dollars
sale price = 36% of x = 0.36*x = 72
0.36*x = 72
x = 72/0.36
x = 200
The original price is $200
discount = 64% of 200 = 0.64*200 = 128
You save $128
The amount you pay is 200-128 = 72 dollars, which matches with the given sale price.