Question

7/2=x/4; 1,5:2=x:8; 2,1/2:1,1/4=2:x.

Answer 1

$\frac{7}{2} = \frac{x}{4} \\ 28 = 2x \\ 2x = 28 \\ x = 28 \div 2 \\ x = 14$

$\frac{1.5}{2} = \frac{x}{8} \\ 4 = 2x \\ 2x = 4 \\ x = 4 \div 2 \\ x = 2$

$\frac{ \frac{5}{2} }{ \frac{5}{4} } = \frac{2}{x} \\ \frac{2}{4} = \frac{5}{2} x \\ x = \frac{2}{4} \div \frac{5}{2} \\ x = \frac{2}{4} \times \frac{2}{5} \\ x = \frac{4}{20} \\ x = \frac{1}{5}$