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$The mean and variance of ' n'observations x_{1}, x_{2}, x_{3}, \dots, x_{n} are 6 and 0, respectively. If$ $\sum_{i = 1}^{n} x_{i}^{2} = 900, then the value of n is equal to$

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Correct option is B

Given mean x¯=6 and variance σ2=∑i=1n xi−x¯2n=0⇒x1−62+x2−62+……+xn−62=0⇒x1=x2=……..=xn=6 ( ∵ Sum of perfect squares will be zero, when each of them is zero) Given that ∑i=1n xi2=900⇒n⋅62=900∴n=25

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The mean and variance of ' n 'observations x1,x2,x3,…,xn are 6 and 0, respectively. If ∑i=1n xi2=900, then the value of n is equal to

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$The mean and variance of ' n'observations x_{1}, x_{2}, x_{3}, \dots, x_{n} are 6 and 0, respectively. If$ $\sum_{i = 1}^{n} x_{i}^{2} = 900, then the value of n is equal to$