281430. Вычислите: a) (\(\frac{1}{8} + \frac{3}{4}\)) \(\cdot\) 16; б) 12\(\frac{1}{2}\) : 2\(\frac{1}{2}\) - 6; в) 2 : 2\(\frac{1}{3}\); г) \(\frac{3}{4}\) \(\cdot\) \(\frac{5}{7}\) + \(\frac{3}{4}\) \(\cdot\) \(\frac{2}{7}\).

Ответ:

a) (\( \frac{1}{8} + \frac{3}{4} \)) \(\cdot\) 16 = (\(\frac{1}{8} + \frac{6}{8}\)) \(\cdot\) 16 = \(\frac{7}{8}\) \(\cdot\) 16 = 14

б) 12\(\frac{1}{2}\) : 2\(\frac{1}{2}\) - 6 = \(\frac{25}{2}\) : \(\frac{5}{2}\) - 6 = \(\frac{25}{2}\) \(\cdot\) \(\frac{2}{5}\) - 6 = 5 - 6 = -1

в) 2 : 2\(\frac{1}{3}\) = 2 : \(\frac{7}{3}\) = 2 \(\cdot\) \(\frac{3}{7}\) = \(\frac{6}{7}\)

г) \(\frac{3}{4}\) \(\cdot\) \(\frac{5}{7}\) + \(\frac{3}{4}\) \(\cdot\) \(\frac{2}{7}\) = \(\frac{3}{4}\) \(\cdot\) (\(\frac{5}{7}\) + \(\frac{2}{7}\)) = \(\frac{3}{4}\) \(\cdot\) \(\frac{7}{7}\) = \(\frac{3}{4}\) \(\cdot\) 1 = \(\frac{3}{4}\)

Доп. профит: