(3√200-1/2√18+1/5√50):√8

[latex](3\sqrt{200}- \frac{1}{2}\sqrt{18}+ \frac{1}{5} \sqrt{50}):\sqrt8= (30\sqrt2-\frac{3}{2}\sqrt2+\frac{1}{5}\cdot 5\sqrt2):2\sqrt2=\\\\=\sqrt2(30-\frac{3}{2}+1):2\sqrt2= \frac{\sqrt2\cdot 29,5}{2\sqrt2} = \frac{29,5}{2} =14,75[/latex]