5.541 Вычислите: a) 5:$$\frac{2}{3}$$; б) $$\frac{3}{8}:\frac{1}{3}$$; B) $$\frac{1}{12}:\frac{5}{36}$$

а)

\begin{aligned} 5 : \frac{2}{3} &= \frac{5}{1} : \frac{2}{3} = \frac{5}{1} \cdot \frac{3}{2} = \frac{5 \cdot 3}{1 \cdot 2} = \frac{15}{2} = 7\frac{1}{2} \end{aligned}

б)

\begin{aligned} \frac{3}{8} : \frac{1}{3} &= \frac{3}{8} \cdot \frac{3}{1} = \frac{3 \cdot 3}{8 \cdot 1} = \frac{9}{8} = 1\frac{1}{8} \end{aligned}

в)

\begin{aligned} \frac{1}{12} : \frac{5}{36} &= \frac{1}{12} \cdot \frac{36}{5} = \frac{1 \cdot 36}{12 \cdot 5} = \frac{36}{60} = \frac{3 \cdot 12}{5 \cdot 12} = \frac{3}{5} \end{aligned}