The mean of the following frequency distribut | vedclass

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(B) To find the mean of a grouped frequency distribution,we use the formula $\bar{x} = \frac{\sum f_i x_i}{\sum f_i}$.First,calculate the class marks

Vedclass · Accepted Answer

$18$

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(B) To find the mean of a grouped frequency distribution,we use the formula $\bar{x} = \frac{\sum f_i x_i}{\sum f_i}$.First,calculate the class marks $(x_i)$ for each interval:$0-20: x_1 = 10$$20-40: x_2 = 30$$40-60: x_3 = 50$$60-80: x_4 = 70$$80-100: x_5 = 90$$100-120: x_6 = 110$Now,calculate $\sum f_i x_i = (10 	imes 10) + (f 	imes 30) + (7 	imes 50) + (6 	imes 70) + (5 	imes 90) + (4 	imes 110) = 100 + 30f + 350 + 420 + 450 + 440 = 1760 + 30f$.Calculate $\sum f_i = 10 + f + 7 + 6 + 5 + 4 = 32 + f$.Given the mean $\bar{x} = 46$,we have $46 = \frac{1760 + 30f}{32 + f}$.$46(32 + f) = 1760 + 30f$$1472 + 46f = 1760 + 30f$$46f - 30f = 1760 - 1472$$16f = 288$$f = \frac{288}{16} = 18$.

Class	$0-20, 20-40, 40-60, 60-80, 80-100, 100-120$
Frequency	$10, f, 7, 6, 5, 4$

Class	$1-3$	$3-5$	$5-7$	$7-10$
Frequency	$9$	$22$	$27$	$17$

The mean of the following frequency distribution is $46$. Find the missing frequency $f$.

Class $0-20, 20-40, 40-60, 60-80, 80-100, 100-120$

Frequency $10, f, 7, 6, 5, 4$

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The mean of the following frequency distribution is $46$. Find the missing frequency $f$. Class $0-20, 20-40, 40-60, 60-80, 80-100, 100-120$ Frequency $10, f, 7, 6, 5, 4$