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 Question from Michelle, a student: Good day, I would like to know if there is a particular equation to validate the following information: I had to find the original cost of an item sold for 759.36$before a 25% discount and 13% taxes. I know we must use separate equations to obtain the answer but I am unsure how to write the equation to validate my answer. please advise, Thank-you Michelle Hi Michelle, If I understand this correctly you paid$759.36\$$and this included a 13% tax and a discount of 25%. If this is correct then you went to the cashier with the discounted price, the cash register added the 13% tax and the cashier said you owed 759.36\. Suppose the discounted price was D\$$ then the cash register calculated

$D\ + 0.13 \times D\ = 1.13 \times D\ = 759.36\$

and hence

$D\ = \frac{759.36\}{1.13}.$

How much is this?

Suppose the original price was $P\$$then the discount is 25% so the discounted price D\$$ was 75% of$P\$.$ Solve for $P\$.\$

Penny

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