Answer: 64.39 dollars
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Step-by-step explanation:
Before the discount, he would spend 59.99+32 = 91.99 dollars. This is before sales tax is added.
However, he gets 30% off, so he saves 0.30*91.99 = 27.597 = 27.60 dollars.
Meaning that he actually spends 91.99 - 27.60 = 64.39 dollars
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As a shortcut, we can multiply 91.99 by 0.70 to get 64.393 which rounds to 64.39
The 0.70 is due to the fact that if he saves 30%, then he still has to pay the remaining 70%
Keep in mind that sales tax would need to be added on; however, your teacher doesn't mention the sales tax rate.