Asweater for $36.00 at 7% sales tax

Convert 7% to a decimal: 0.07 
Sales Tax = $36.00 x 0.07 = $2.52 
Total = $36.00 x 1.07 = $38.52 

I use 1.07 for the total because you need ($36.00 x 1) for the actual price of the product, plus ($36.00 x 0.07) for the tax part, so: 
($36.00 x 1) + ($36.00 x 0.07) = $36.00(1 + 0.07) = $36.00 x 1.07 = $38.52

36.00 * .07 = 2.52 in sales tax 
Price of sweater 36.00
Sales tax              2.52
Total cost            38.52 

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