When operating a business it is imperative that you calculate tax rates along with sales and the salary you are paying your employees. Without properly calculating this amount, you can leave your business seriously short at payroll or tax time. Many Sharp calculators have a function that allows the user to set a tax rate so that it is automatically calculated when used. You will get a "sub-total" and then a "total" amount. The method of setting the Sharp calculator may vary slightly from model to model, but many of them can be set using these instructions.

Turn on the calculator and clear it a few times. You want to make sure that there is no residual calculation. Hit the "C" or "C/CE" button on the calculator several times so that "0" is showing on the screen.

Slide the switch into the "tax rate" setting. Many Sharp calculators have a sliding switch that allows you to set a few different constants. This is usually located toward the top of the calculator. Move the switch until it is locked under "tax rate."

Input the numeric value of the tax rate. For instance, if the tax rate is 7 per cent, enter 7. If the tax rate has a fraction, enter it in decimal form. For example, if the tax rate is 5 1/2 per cent, enter "5.5." Do not hit the "percent" key after entering this number.

Press the "tax plus" key. This means you are calculating this amount on top of the price. So if several store items add up to £32 and the tax is 5 per cent, the calculator will compute the amount at £34.10.

Slide the "tax rate" button back to the starting position, which is usually signified by a round dot on the slide bar.

Repeat these steps for the "tax minus" button. For instance, if you want to always subtract the sales tax from the total to determine your actual sales, you would want to subtract the tax rate. Simply slide the bar, enter the tax rate, and press the "tax minus" before sliding the bar back. In the above example, if the sales totalled £34.10, the tax minus button would allow you to see that the actual sales were £32.