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If the mean of first n natural numbers i...

If the mean of first `n` natural numbers is `(5n)/9` , then `n=` (a) 5 (b) 4 (c) 9 (d) 10

A

5

B

4

C

9

D

None of these

Text Solution

Verified by Experts

The correct Answer is:
C
Sum of the first n natural numbers is `(n(n + 1))/(2)`.
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PEARSON IIT JEE FOUNDATION-STATISTICS-LEVEL-1
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  14. The mean deviation of first 8 composite numbers is .

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