Tìm phím % trên máy tính. Thực hành sử dụng phím % để quy đổi số thập phân. Dùng phím % để tính toán.

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Most simple calculators will contain a key with the % symbol. More advanced, graphing calculators may not have this key because the makers expect that you can operate without it. But many more basic calculators will have it. The simplest use of the % key is to convert any number from its percentage form to its decimal form. Just enter the number and press the % button, and the calculator will show the decimal equivalent. The % key on your calculator makes certain calculations very simple. Suppose you want to calculate a tip amount, and you want to find 15% of the total bill of $75.32. If you have your calculator available, you will enter the buttons 15% x 75.32. You should get the result of 11.298, which represents a tip of $11.30.  Whenever you are using a calculator for percentage calculations, you should make sure to press the Clear (C) or All Clear (AC) button before starting. As you enter the numbers for this calculation, you should notice that as soon as your hit the % button, your number of 15 converts to .15. The calculator will the proceed to calculate .15 x 75.32.