Ответ:
Решение:
а) \( 3\frac{3}{4} \times \frac{12}{15} = \frac{15}{4} \times \frac{12}{15} = \frac{15 \cdot 12}{4 \cdot 15} = \frac{12}{4} = 3 \)
б) \( 5\frac{5}{12} \times \frac{9}{65} = \frac{65}{12} \times \frac{9}{65} = \frac{65 \cdot 9}{12 \cdot 65} = \frac{9}{12} = \frac{3}{4} \)
в) \( 10\frac{1}{9} \times \frac{9}{91} = \frac{91}{9} \times \frac{9}{91} = \frac{91 \cdot 9}{9 \cdot 91} = 1 \)
г) \( 1\frac{1}{13} \times \frac{13}{14} = \frac{14}{13} \times \frac{13}{14} = \frac{14 \cdot 13}{13 \cdot 14} = 1 \)
д) \( 1\frac{2}{13} \times \frac{13}{15} = \frac{15}{13} \times \frac{13}{15} = \frac{15 \cdot 13}{13 \cdot 15} = 1 \)
е) \( 2\frac{22}{23} \times \frac{23}{68} = \frac{68}{23} \times \frac{23}{68} = \frac{68 \cdot 23}{23 \cdot 68} = 1 \)
ж) \( 12\frac{1}{4} \times \frac{4}{49} = \frac{49}{4} \times \frac{4}{49} = \frac{49 \cdot 4}{4 \cdot 49} = 1 \)
з) \( 3\frac{1}{3} \times \frac{3}{10} = \frac{10}{3} \times \frac{3}{10} = \frac{10 \cdot 3}{3 \cdot 10} = 1 \)
и) \( 6\frac{6}{7} \times \frac{7}{48} = \frac{48}{7} \times \frac{7}{48} = \frac{48 \cdot 7}{7 \cdot 48} = 1 \)
