How do you add fractions with different denominators?
To add fractions with different denominators, find a common denominator by multiplying the two denominators together (or finding the LCD). Then convert each fraction: multiply each numerator by the other fraction's denominator. Add the new numerators and place the sum over the common denominator. Finally, simplify by dividing numerator and denominator by their GCD. For example, 1/3 + 1/4 = 4/12 + 3/12 = 7/12.