Fractions II Summary
To put fractions in order of size, first change them into equivalent fractions with common denominators.
To find common denominators, first see if one is a factor of the other, if not multiply the two denominators together.
e.g. 2/5 and 7/20 can also be written 8/20 and 7/20.
e.g. 1/3 and 3/7 are equivalent to 7/21 and 9/21.
To add fractions, first change to common denominators, then add the numerators. Simplify if possible.
To subtract fractions, as with adding find common denominators, then subtract the numerators! If possible, simplify.
Related topic: percentages as fractions