Fractions and decimals are simply two different ways of expressing a number. A fraction expresses a number in the form of two other numbers, where the top number in the fraction is being divided by the bottom number. ie. if the fraction was written as x/y, then the fraction would be expressing the number x divided by the number y. A decimal, on the other hand is an expression of a number in a more traditional form, in one single line of numbers, with a decimal point preceeding all of it. To convert a fraction to a decimal, we do what the fraction says, in that we divide the top number by the bottom number. For example, the fraction 3/4 (3 quarters) = 0.75, as 3 divided by 4 = 0.75. The reason we use fractions and dont just make everything a decimal, is that sometimes it is easier to calculate something or express a number using a fraction. For example, when working with irrational numbers, the decimal is actually infinite, so it is impossible to write as a decimal and be 100% accurate, however if written as a fraction, it can be expressed exactly. For example the fraction 1/3 = 0.333333 where the 3s continue forever :))