Fractions, decimals, and percent are all the same thing except different names and are expressed differently. If I have 1/2 it is the same as .5 and 50%. Fractions tell how much you have of that number. Like if I took a pie and divided in to 4ths it would be 1/4, this / means out of the number of fractions in that number. In decimals this place .1 is the tenths. In this place .01 this is the hundredths place. And this place .001 is the thousandths place and so forth. 50%(percent) is equal to .50 and 50/100. 50% means 50% of the pie was eaten. Adding and subtracting decimals is easy and hard so it's medium. 1 whole 1.0 Half of 1 whole is .5 or .50 or .500. Half of .500 is .250 or .25 is half of .50. Fractions, decimals, and percent have been around for millions of years.