Question

Qual o valor de x nessa proporção?
a) $\frac{1}{2} : \frac{2}{7} = \frac{3}{4} : x$

Answer 1

$\frac{1}{2} : \frac{2}{7} = \frac{3}{4} : \frac{x}{1} = \frac{1}{2} . \frac{7}{2} = \frac{3}{4} . \frac{x}{1} =  \frac{7}{4} = \frac{3x}{4} = 4.7=4.3x= 28=12x= x=48/12 x=4$