Найдите значение выражений: a) 1/4•4/9 b) 1/7 • 2 1/3 в) 2 2/5 • 5/6 г) (1/5+ 2/15) • 3/4...

Решите задачу:

$\frac{1}{4} * \frac{4}{9}= \frac{1*4}{4*9}= \frac{1}{9}$

$\frac{1}{7} * 2\frac{1}{30}= \frac{1}{7} * \frac{2*30+1}{30}= \frac{1}{7} * \frac{61}{30}= \frac{1*61}{7*30}= \frac{61}{210}$

$2 \frac{2}{5} * \frac{5}{6}= \frac{5*2+2}{5} * \frac{5}{6}= \frac{12}{5} * \frac{5}{6}= \frac{12*5}{5*6}= \frac{2*6*5}{5*6}= \frac{2}{1}=2$

$(\frac{1}{5} + \frac{2}{15})* \frac{3}{4} = (\frac{1*3}{5*3} + \frac{2}{15})* \frac{3}{4} = (\frac{3}{15} + \frac{2}{15})* \frac{3}{4} = \frac{3+2}{15}* \frac{3}{4} = \frac{5}{15}* \frac{3}{4} =$ $\frac{5}{5*3}* \frac{3}{4} = \frac{1}{3}*\frac{3}{4} = \frac{1*3}{3*4}= \frac{1}{4}$