Ignore the decimal and do long division. When calculating the answer to division problems that contain decimals, it is easier to first perform the math, then go back and add the decimals.
Count the number of digits to the right of the decimal in your original division problem. For example, if your division problem was 54.804 divided by 12, you would have three digits that are to the right of the decimal in your problem.
Place the decimal in your answer with the same number of digits to the right of the decimal as in your problem. Using the example problem, 54.084 divided by 12, you had three digits to the right of the decimal in your problem, so you should have three digits to the right of the decimal in your answer as well. Without the decimals the answer is 4567 but ensure three digits to the right of the decimal point gives us 4.567. Note that zeros to the end of your number do not change the value. For example, 3.34 is equal to 3.3400.
Move the decimal as many places to the right as necessary to make a number a whole number, if you are dividing by a number with a decimal. For example, if your divisor is 2.45, you would need to move the decimal two places to the right to make the whole number 245. If your dividend is a whole number with an understood decimal -- meaning there is an imaginary decimal just to the right of the last digit -- add zeros, then move the decimal the same amount of spaces to the right as you did with your divisor.