When turning in time cards or calculating time cards, employees and their employers frequently find themselves having to convert the number of hours and minutes worked to decimal time, calculated to the hundredths decimal place, or two places after the decimal point in decimal time.
In decimal time, also known as French Revolutionary Time, the hours of the day are divided into 10 decimal hours and each decimal hour has 100 decimal minutes. Scientists and computer programmers also use decimal time to calculate fractional days.
Determine the number of minutes that need to be calculated. There are 60 minutes in one hour in standard time (the 24-hour day cycle, with 60 minutes per hour). Reserve the full number of hours for later and divide the number of minutes by 60.
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For example, if you have five hours and 30 minutes, reserve the five hours for later and divide the 30 minutes by 60 for a total of 0.5. Write this value down using a pencil and paper, making note that you also have five hours.
Write down the number of hours you calculated. For this example, use five hours. Write a decimal point after the five. Write down the value you calculated in Step 1 on the right-hand side of the decimal. For the example, you would have 5.5.
Convert the value to hundredths. In the example, to convert 5.5 to a hundredths decimal calculation, simply write a "0" down after the final 5. Other minute calculations will have the decimal place built in. For example, 45 minutes divided by 60 equals 0.75, a value that is already calculated to hundredths. Some values will be calculated beyond the hundredths place. In this case, round the hundredths spot, and the answer is your value.
To round the hundredths spot, look at the third number past the decimal place. This is the thousandths place. If the value is five or greater, add one to the hundredths spot. If the value is less than five, keep the number in the hundredths spot the same.