Решите пожалуйста два задания, и я вам помогу

Решите задачу:

$\frac{x}{4}= \frac{25}{5}$

$x= \frac{4*25}{5} = \frac{100}{5} = 20$

$\frac{70}{x}= \frac{20}{2}$

$x= \frac{70*2}{20} = \frac{140}{20} = 7$

$\frac{30}{x}= \frac{36}{6}$

$x= \frac{30*6}{36} = \frac{180}{36} = 5$

$\frac{x}{5}= \frac{16}{4}$

$x= \frac{5*16}{4} = \frac{80}{4} = 20$

$\frac{140}{x}= \frac{40}{2}$

$x= \frac{140*2}{40} = \frac{280}{40} = 7$

$\frac{x}{12}= \frac{5}{6}$

$x= \frac{12*5}{6} = \frac{60}{6} = 10$

$\frac{48}{x}= \frac{30}{25}$

$x= \frac{48*25}{30} = \frac{1200}{30} = 40$

$\frac{17}{3}= \frac{x}{9}$

$x= \frac{17*9}{3} = \frac{153}{3} = 51$