Question

If $\sqrt{7}=2.646$, then$\frac{1}{\sqrt{7}}$=?
(a) 0.375
(b) 0.378
(c) 0.441
(d) none of these

Answer 1

(b) 0.378
∵$\sqrt{7}$ = 2.646
We have:
$$\begin{gathered} \frac{1}{\sqrt{7}} \\ =\frac{1}{\sqrt{7}}\times \frac{\sqrt{7}}{\sqrt{7}} \\ =\frac{\sqrt{7}}{7} \\ =\frac{2.646}{7} \\ =0.378 \end{gathered}$$