Nick paid $68.25 for a coat, including sales tax of 5%. What was the original price of the coat before tax?

Since 5% sales tax was added to the cost of the coat, $68.25 is 105% of the original price of the coat. Use a proportion to ?nd the original cost of the coat; part/whole = %/100. Part is the price of the coat with the sales tax, $68.25. Whole is the original price on the coat that we are looking for.

Call it x. The % is 105; 68.25/x = 105/100. To solve for x, cross-multiply; (68.25)(100) = 105x. Divide both sides by 105; 6825/105 = 105x/105; x = $65.00.