[tex] a)\frac{1}{2} + \frac{7}{2} = \frac{1 \times 7}{2 \times 2} = \frac{7}{4} = 1 \frac{3}{4} \\ \\ b) \frac{24}{3} + \frac{25}{6} = 8 + \frac{25}{6} = \frac{8 \times 6}{1 \times 6} + \frac{25}{6} = \frac{48}{6} + \frac{25}{6} = \frac{48 + 25}{6} = \frac{73}{6} \\ \\ c) \frac{24}{5 \times 4} = \frac{24}{20} = \frac{6}{5} \\ \\ \frac{24}{5} \times 4 = \frac{24}{5} \times \frac{4}{1} = \frac{24 \times 4}{5 \times 1} = \frac{96}{5} = 19 \frac{1}{5} [/tex]
