а) $$ \frac{x}{46} = \frac{12}{23} $$
$$ x = \frac{12 \cdot 46}{23} = \frac{12 \cdot 2 \cdot 23}{23} = 12 \cdot 2 = 24$$
б) $$ \frac{5}{6} = \frac{h}{36} $$
$$ h = \frac{5 \cdot 36}{6} = 5 \cdot 6 = 30$$
г) $$ \frac{8}{y} = \frac{72}{72} $$
$$ y = \frac{8 \cdot 9}{72} = \frac{72}{72} = 9$$
д) $$ \frac{18}{d} = \frac{3}{5} $$
$$ d = \frac{18 \cdot 5}{3} = 6 \cdot 5 = 30$$
Ответ: a) 24; б) 30; г) 9; д) 30.