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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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Knowledge Check

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    A
    3
    B
    7
    C
    9
    D
    any natural number

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    2000
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    not possible

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    B
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    C
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    D
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