Question

the mean of first n odd natural numbers is n2/81,then n=

Answer 1

sum of first n odd natural numbers is = n^2
mean of first n odd natural numbers is = n^2/n
$\frac{ {n}^{2} }{n} = \frac{ {n}^{2} }{81} \\ n = 81$

Answer 2

Answer:

$Value \: of \: n = 81$

Step-by-step explanation:

$Sum \: of \: n \: odd\\ \: natural\:numbers = n^{2}$

According to the problem given,

The mean of first n odd natural numbers is n2/81

$\implies mean = \frac{n^{2}}{81}$ /* given

$\implies \frac{Sum \: of \: observations }{Number \: of \: observations }=\frac{n^{2}}{81}$

$\implies \frac{n^{2}}{n}= \frac{n^{2}}{81}$

After cancellation , we get

$\implies \frac{1}{n}=\frac{1}{81}$

$\implies n = 81$

Therefore,

$Value \: of \: n = 81$

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