Answer:
1) 9/10 + 4/5 + 5/6 = 2 8/15
2) 14/15 + 2/9 + 1/5 = 1 16/45
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Solution:
[tex] \bold{1)} \: \tt \frac{9}{10} + \frac{4}{5} + \frac{5}{6} \\ \\⟹ \tt \frac{9}{10} + \frac{4}{5} \\ = \tt \frac{9 \times 1}{10 \times 1} + \frac{4 \times 2}{5 \times 2} = \frac{9 + 8}{10} = \frac{17}{10} \\ \\ ⟹\tt \frac{17}{10} + \frac{5}{6} \\ = \tt \frac{17 \times 3}{10 \times 3} + \frac{5 \times 5}{6 \times 5} = \frac{51 + 25}{30} = \frac{76}{30} \: or \: 2 \frac{16}{30} = 2 \frac{8}{15} \\ \\ \\ \\ \bold{2)} \tt \: \: \frac{14}{15} + \frac{2}{9} + \frac{1}{5} \\ \\⟹ \tt \frac{14 \times 3}{15 \times 3} + \frac{2 \times 5}{9 \times 5} = \frac{42 + 10}{45} = \frac{52}{45} \\ \\⟹ \tt \frac{52}{45} + \frac{1}{5} \\ = \frac{52 \times 1}{45 \times 1} + \frac{1 \times 9}{5 \times 9} = \frac{52 + 9}{45} = \frac{61}{45} = 1 \frac{16}{45} [/tex]
