The variance of the following continuous freq | vedclass

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(D) First,calculate the mean $\bar{x}$:$\bar{x} = \frac{\sum f_i x_i}{\sum f_i} = \frac{(5 	imes 2) + (15 	imes 3) + (25 	imes 4) + (35 	imes 1)}{

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$84$

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(D) First,calculate the mean $\bar{x}$:$\bar{x} = \frac{\sum f_i x_i}{\sum f_i} = \frac{(5 	imes 2) + (15 	imes 3) + (25 	imes 4) + (35 	imes 1)}{2 + 3 + 4 + 1} = \frac{10 + 45 + 100 + 35}{10} = \frac{190}{10} = 19$.Next,calculate the variance $\sigma^2 = \frac{\sum f_i (x_i - \bar{x})^2}{N}$:$\sigma^2 = \frac{2(5-19)^2 + 3(15-19)^2 + 4(25-19)^2 + 1(35-19)^2}{10}$$\sigma^2 = \frac{2(-14)^2 + 3(-4)^2 + 4(6)^2 + 1(16)^2}{10}$$\sigma^2 = \frac{2(196) + 3(16) + 4(36) + 1(256)}{10}$$\sigma^2 = \frac{392 + 48 + 144 + 256}{10} = \frac{840}{10} = 84$.Thus,the variance is $84$.

Class Interval	$0-10$	$10-20$	$20-30$	$30-40$
Frequency	$2$	$3$	$4$	$1$

The variance of the following continuous frequency distribution is
Class Interval $0-10$ $10-20$ $20-30$ $30-40$
Frequency $2$ $3$ $4$ $1$

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The variance of the following continuous frequency distribution isClass Interval$0-10$$10-20$$20-30$$30-40$Frequency$2$$3$$4$$1$