To write fractions as decimals divide the numerator by the denominator, for example 3/4 3 divided by 4 equals 0.75 so 3/4 as a decimal is 0.75. If you want to do that with a mixed number, 3 3/4 3 divided by 4 equals 0.75 then add the 3 so 3 3/4 is equal to 3.75.