# A phone bill is $89.75 including taxes, it was $85.50 before tax. What percent of sales tax was paid?

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### 4 Answers

- ?Lv 57 years agoFavorite Answer
There is a formula: %/100 = is/of

First: 89.75 - 85.50 = $4.25. That is the sales tax.

So the question is: What percent pf $89.75 is $4.25.

x/100 = 4.25/89.75 (is/of)

cross multiply

89.75x = 100 * 4.25

89.75x = 425

divide by 89.75

x = 425/89.75

x = 4.735...

x = 4.7%

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- Andrew W.Lv 47 years ago
SubTotal + SubTotal*SalesTaxRate = Total

Total: $89.75

SubTotal: 85.50

SalesTaxRate: r

85.50 + 85.50*r = 89.75

85.50*r = 4.25

r = .0497

Writing the SalesTaxRate as a percentage:

4.97%

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- bransfordLv 44 years ago
I assaume Sam and Joe are an identical person or a minimum of get an identical deal. a million. proportion revenues tax: ((ninety.ninety 5 - 80 5)/80 5)*one hundred = 7 Joe paid 7% revenues tax. 2.As a proportion of ninety.ninety 5 ((ninety.ninety 5 - 80 5)/ninety.ninety 5)*one hundred = 6.fifty 4 Sam paid 6.fifty 4% of ninety.ninety 5 revenues tax.

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