Percentage

Question

In Chinatown, Kevin offered a salesperson $150 for a coat. The offer included the 7.5% sales tax. If the salesperson accepts the offer , what would be the price of the coat, to the nearest dollar, before tax?

Answer 1

$150 - 7.5% = $11.25

 

$150 - $11.25 = $138.75 -> $139.00 

Answer 2

PriceAfterTax = PriceBeforeTax + Tax

or

PriceBeforeTax = PriceAfterTax - Tax

1. Do you see why the two equations above are equivalent?

2. Can you figure out the tax and then plug in to either equation and get the answer?

Answer 3

x=price of the coat

x+(7.5%)x=150

x+0.075x=150

1.075x=150

1075x=150,000

x=150,000/1075

x=$139.53 which rounds to $140

or,...

1.075x=150

1 75/1000=150

(1 3/40)x=150

(43/40)x=150

(40/43)(43/40)x=(40/43)(150

x=6000/43

x=$139.53 again which becomes $140