###
**Find the average of cubes of first 49 positive integers.**

A. 30625
B. 1225
C. 30125
D. 6235
**Answer: Option A**

## Show Answer

Solution(By Apex Team)

Sum of cubes of first n positive consecutive numbers is $\Large=\frac{(n(n+1))^{2}}{4}$
$\begin{array}{l}\text{ Average }\\
=\Large\frac{(n(n+1))^2}{4}\\
\Rightarrow n=49\\
\Rightarrow\Large\frac{49(50)^2}{4}\\
\Rightarrow30625\end{array}$

## Related Questions On Average

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