Find the average of cubes of natural num

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Home Questions F2JT67924A

Target Exam

CUET

Subject

General Test

Chapter

Numerical Ability

Topic

Average

Question:

Find the average of cubes of natural numbers till 7.

Options:

115

110

112

140

Correct Answer:

112

Explanation:

Sum of cube of n natural numbers = n² × \(\frac{(n + 1)(n + 1)}{4}\)

Here n = 7

Sum of cube of 7 natural numbers = 7² × \(\frac{(7 + 1)(7 + 1)}{4}\) = 784

Now, the average of cube of first 7 natural numbers= \(\frac{784}{7}\) = 112