Question

Aflati x din proportiile : 2/1/5 =20/x

Answer 1

$\sf \frac{2}{\frac{1}{5}}= \frac{20}{x} \\ \\ 2*5= \frac{20}{x} \\ \\ \frac{20}{x}=10 \\ \\x= \frac{20}{10} \\ \\ \boxed{\sf x=2}$

Answer 2

2/1/5=20/x<=>10=20/x=>x=2