Question

Найдите x из пропорции 2/5:x=12/25:3/10

Answer 1

$\frac{2}{5}:x=\frac{12}{25}:\frac{3}{10} \\\\x=\frac{\frac{2}{5}\cdot \frac{3}{10}}{\frac{12}{25}}\\\\x=\frac{2\cdot 3\cdot 25}{5\cdot 10\cdot 12}\\\\x=\frac{1}{4}\\\\x=0,25$

Answer 2

2/5:x=12/25:3/10
2/5*3/10=12/25*x
6/50=12/25*x
12x=3
x=3/12
x=1/4