[tex] \frac{3}{4} + \frac{4}{5} [/tex]Step 1: Find the least common denominator (LCD) of 4 and 5.The LCD of 4 and 5 is 20.Step 2: Rewrite the fractions with the common denominator.[tex] \frac{3}{4} = \frac{15}{20}, \quad \frac{4}{5} = \frac{16}{20} [/tex]Step 3: Add the numerators.[tex] \frac{15}{20} + \frac{16}{20} = \frac{15 + 16}{20} = \frac{31}{20} [/tex]So, the final answer is:[tex] \frac{31}{20} [/tex]