Question

If cost of $8$ pencils is ${28}^{1/2}$, find the cost of $1$ pencil.

Answer 1

8 pencils $\to \sqrt{28}$

1 pencil $\to \frac{\sqrt{28}}{8}=\frac{\sqrt{4\times 7}}{8}=\frac{2\sqrt{7}}{8}=\frac{\sqrt{7}}{4}$