Question

Find the mean proportional between $\text{7 and 28}$.

Answer 1

Step:To find mean proportional.

Let the mean proportional between $\text{7 and 28}$ is $\text{a}$, it means,

$\text{7:a::a:28}$ becomes in proportion

We know that , $\text{Product of extremes terms = Product of means terms}$

$$\begin{gathered} \Rightarrow a\times a=7\times 28 \\ \Rightarrow a^2=196 \\ \Rightarrow a=\sqrt{196} \\ \Rightarrow a=14 \end{gathered}$$

Hence, the mean proportional between $\text{7 and 28}$ is $14$.