Question

помогите пожалуйста!!!!!!!!!!
$5.7 - \frac{3}{4}$
$2\frac{1}{3} \div \frac{1}{3}$
$\frac{6.4}{0.4 + 2.8}$

Answer 1

$5.7 - \frac{3}{4} = 5.70 - 0.75= 4.95 \\ \\ 2 \frac{1}{3} : \frac{1}{3} = \frac{7}{3} * \frac{3}{1} = \frac{7}{1} =7 \\ \\ \frac{6,4}{0,4+2,8} = \frac{6,4}{3,2} = \frac{2}{1} =2$