Вопрос:

Выполните умножение: а) 1 3/7 · 1 1/4; б) 3 1/5 · 3/8; в) 9 · 4 1/6; г) 3 17/21 · 3 1/8; д) 16 2/3 · 1 1/5; е) 5 2/5 · 3 1/3; ж) 1 2/7 · 1 1/4; з) 2 3/4 · 3 1/3; и) 3 1/3 · 3 3/5; к) 6 1/2 · 1 1/39.

Ответ:

а) \(1\frac{3}{7}\cdot1\frac{1}{4}=\frac{10}{7}\cdot\frac{5}{4}=\frac{25}{14}=1\frac{11}{14}\).

б) \(3\frac{1}{5}\cdot\frac{3}{8}=\frac{16}{5}\cdot\frac{3}{8}=\frac{6}{5}=1\frac{1}{5}\).

в) \(9\cdot4\frac{1}{6}=9\cdot\frac{25}{6}=\frac{75}{2}=37\frac{1}{2}\).

г) \(3\frac{17}{21}\cdot3\frac{1}{8}=\frac{80}{21}\cdot\frac{25}{8}=\frac{250}{21}=11\frac{19}{21}\).

д) \(16\frac{2}{3}\cdot1\frac{1}{5}=\frac{50}{3}\cdot\frac{6}{5}=20\).

е) \(5\frac{2}{5}\cdot3\frac{1}{3}=\frac{27}{5}\cdot\frac{10}{3}=18\).

ж) \(1\frac{2}{7}\cdot1\frac{1}{4}=\frac{9}{7}\cdot\frac{5}{4}=\frac{45}{28}=1\frac{17}{28}\).

з) \(2\frac{3}{4}\cdot3\frac{1}{3}=\frac{11}{4}\cdot\frac{10}{3}=\frac{55}{6}=9\frac{1}{6}\).

и) \(3\frac{1}{3}\cdot3\frac{3}{5}=\frac{10}{3}\cdot\frac{18}{5}=12\).

к) \(6\frac{1}{2}\cdot1\frac{1}{39}=\frac{13}{2}\cdot\frac{40}{39}=\frac{20}{3}=6\frac{2}{3}\).