Question

The mean of the first five multiples of $3$ is-

• A. $3$
• B. $9$
• C. $12$
• D. $15$

Answer 1

The correct option is B

$9$

The first five multiples of $3$ are $3,6,9,12,15$

Sum of multiples $=3+6+9+12+15$

$=45$

Number of terms $=5$

Therefore,

Mean $=\frac{\mathbf{S}\mathbf{u}\mathbf{m}\mathbf{}\mathbf{o}\mathbf{f}\mathbf{}\mathbf{m}\mathbf{u}\mathbf{l}\mathbf{t}\mathbf{i}\mathbf{p}\mathbf{l}\mathbf{e}\mathbf{s}}{\mathbf{N}\mathbf{u}\mathbf{m}\mathbf{b}\mathbf{e}\mathbf{r}\mathbf{}\mathbf{o}\mathbf{f}\mathbf{}\mathbf{t}\mathbf{e}\mathbf{r}\mathbf{m}\mathbf{s}}$

$$\begin{gathered} =\frac{45}{5} \\ =9 \end{gathered}$$

So, The mean of the first five multiples of $3$ is $9$

Hence, option B is correct