Question

Зделайте пожалуйста без скама прошу

Answer 1

1.

$1) \: \frac{2}{3} \times \frac{9}{10} = \frac{3}{5} \\ 2) \: 2 \frac{3}{5} \times 1 \frac{9}{26} = \frac{13 \times 35}{5 \times 26} = \frac{7}{2} = 3 \frac{1}{2} \\ 3) \: \frac{7}{19} \times 57 = 7 \times 3 = 21$

2.

$15 \times \frac{3}{5} = 3 \times 3 = 9 \: \: km$

3.

$1 \frac{4}{9} \times 1 \frac{5}{13} - 2 \frac{1}{12} \times \frac{4}{15} = \frac{13 \times 18}{9 \times 13} - \frac{25 \times 4}{12 \times 15} = \\ = 2 - \frac{5}{3 \times 3} = 2 - \frac{5}{9} = 1 \frac{9}{9} - \frac{5}{9} = 1 \frac{4}{9}$