Question

помогите ( только 5 и 7)​

Answer 1

Ответ:

5.

$1) \frac{5}{6} - \frac{9}{14} = \frac{5\times 7 - 9 \times 3}{42} = \frac{35 - 27}{42} = \frac{8}{42} = \frac{4}{21}$

$2)4 \frac{7}{15} - 2 \frac{11}{20} = \frac{4 \times 15 + 7}{15} - \frac{2 \times 20 + 11}{ 20} = \frac{67}{15} - \frac{51}{20} = \frac{67 \times 4 - 51 \times 3}{60} = \frac{268 - 153}{60} = \frac{115}{60} = \frac{115 \div 5}{60 \div 5} = \frac{23}{12} = 1 \frac{11}{12}$

Вибач, сьоме не знаю (