A percentage is another way of expressing a fraction. Percent literally means "per 100." So when you calculate a percentage, you divide the given amount of something (numerator) by the total amount (denominator), then multiply by 100.
Open the Microsoft Excel program and type the numerator (given amount) into cell A1.
Highlight cell B1.
In the “fx” box in the toolbar at the top of the screen, type “=A1/X” (without the quotes), replacing X with the denominator (the total amount) . For instance, if you are calculating a percentage score out of 60 points, you would type “=A1/60”.
Hit enter. This should calculate a decimal (eg, .75) in cell B1.
Hit the "%" button on the formatting toolbar near the top of the screen to convert to a percentage. Alternatively, you can simply multiply by 100.
You can calculate a series of percentages using the same total amount (denominator) by typing the given amounts (numerators) into column A, then copying cell B1 and pasting into the remaining cells in column B