Question

If $\sqrt{5}=2.236$, then the value of $\frac{\sqrt{5}}{2}-\frac{10}{\sqrt{5}}+\sqrt{125}$ is equal to:

• A. 5.59
• B. 7.826
• C. 8.944
• D. 10.062

Answer 1

Answer: (B)

7.826

$\frac{\sqrt{5}}{2}-\frac{10}{\sqrt{5}}+\sqrt{125}=\frac{(\sqrt{5}{)}^2-20+2\sqrt{5}\times 5\sqrt{5}}{2\sqrt{5}}$
$\frac{5-20+50}{2\sqrt{5}}$
$\frac{35}{2\sqrt{5}}\times \frac{\sqrt{5}}{\sqrt{5}}$
$\frac{35\sqrt{5}}{10}$
$\frac{7\times 2.236}{2}$
$=7\times 1.118$
$=7.826$