14+15\dfrac{1}{4} + \dfrac{1}{5}
14+15\dfrac{1}{4} + \dfrac{1}{5}
Since these fractions have different denominators, we need to find the least common multiple of the denominators
The least common multiple of 4 and 5 is 20, so we need to multiply to make each of the denominators = 20
14∗55=520\dfrac{1}{4} * \dfrac{5}{5} = \dfrac{5}{20}
15∗44=420\dfrac{1}{5} * \dfrac{4}{4} = \dfrac{4}{20}
Since these fractions have the same denominator, we can just add the numerators
520+420=920\dfrac{5}{20} + \dfrac{4}{20} = \dfrac{9}{20}