To find the Inn's nightly cost before tax is added you will divide the total cost of the room $144.16 by the tax rate of 6%. When you divide the tax rate you will move the decimal over and use the number 1.06 (6%). When you divide $144.16 by 1.06 the answer is $136 per night before tax. To check your work you can multiply $136 by 1.06 giving you a total cost of $144.16 after tax.