This is a video that teaches how to add and subtract fractions. For fractions that have like denominators, you simply add the numerator and keep the denominator. Next, you reduce the fraction to its lowest term.
For denominators that are not the same, you first have to find a common denominator. This is done by using the Lowest Common Multiple (LCM) method. You find the lowest common multiple of the denominator and make that the denominator of both fractions. Next, make each fraction equal according to their new denominator. After that, you simply add the new numerators and simplify to the lowest term if needed. For a subtraction problem,
if denominators are the same, you simply subtract the numerators and reduce if possible.