To convert a fraction to a decimal, you divide the numerator by the denominator - on a calculator, or using long division.
Divide the numerator by the denominator
Based on the decimal fraction part it looks like this is a rounded answer to division by three. If so, multiply the whole thing by three on a calculator, round, then convert to a fraction using three for the denominator. Using Windows 7 calculator, 71.6666667 * 3 = 215.0000001. You are probably looking at 215/3 for the answer as an improper fraction, or 71 2/3 as a proper fraction.
Say for example the fraction you wanted to convert was 3 fifths or 3/5. Then you type into your calculator 3 divided by 5. This would give you 0.6 and that is the decimal version!
Fractions are basically a division problem with the line between the numerator and denominator being the division sign. 4/7 means the same thing as 4 divided by 7 and that is how you convert them to decimal form. 4/7 = 0.5714
You should be familiar with long division involving decimals
Multiply the numerator of the fraction by 100 and then divide (using long division if needed or a calculator) by the denominator.
5/8 = 5 divided by 8 = 0.625
That function depends on the calculator's capabilites. Some calculators do not show fractions. They only represent fractions as a decimal value (e.g. 50% is represented in the calculator as .5). If your calculator has a fraction function, you can enter 50% then press the fraction button & it will display 1/2 (which is the lowest fraction for 50%).
Multiply both numbers by five- to get the fraction 85/100... which is 85%