Calculate the mean of the frequency distribut | vedclass

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(A) To calculate the mean,we use the formula $\bar{x} = \frac{\sum f_i x_i}{\sum f_i}$,where $x_i$ is the class mark.$1$. Find the class marks $(x_i)$

Vedclass · Accepted Answer

$27$

Vedclass · Answer

(A) To calculate the mean,we use the formula $\bar{x} = \frac{\sum f_i x_i}{\sum f_i}$,where $x_i$ is the class mark.$1$. Find the class marks $(x_i)$ for each interval:- For $0-10$,$x_1 = (0+10)/2 = 5$- For $10-20$,$x_2 = (10+20)/2 = 15$- For $20-30$,$x_3 = (20+30)/2 = 25$- For $30-40$,$x_4 = (30+40)/2 = 35$- For $40-50$,$x_5 = (40+50)/2 = 45$$2$. Calculate $f_i x_i$:- $20 	imes 5 = 100$- $10 	imes 15 = 150$- $20 	imes 25 = 500$- $30 	imes 35 = 1050$- $20 	imes 45 = 900$$3$. Calculate $\sum f_i x_i = 100 + 150 + 500 + 1050 + 900 = 2700$.$4$. Calculate $\sum f_i = 20 + 10 + 20 + 30 + 20 = 100$.$5$. Mean $\bar{x} = 2700 / 100 = 27$.

Marks	$0-10$	$10-20$	$20-30$	$30-40$	$40-50$
No. of students	$20$	$10$	$20$	$30$	$20$

Weekly income	Number of families
$0-1000$	$250$
$1000-2000$	$190$
$2000-3000$	$100$
$3000-4000$	$40$
$4000-5000$	$15$
$5000-6000$	$5$
Total	$600$

Calculate the mean of the frequency distribution of the marks scored by $100$ students in a mathematics test:

Marks $0-10$ $10-20$ $20-30$ $30-40$ $40-50$

No. of students $20$ $10$ $20$ $30$ $20$

Similar Questions

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The mean of $15$ observations is $16$. If $2$ is added to each observation and then each result is divided by $3$,the new mean is:

Weekly income of $600$ families is tabulated below:

Weekly income Number of families

$0-1000$ $250$

$1000-2000$ $190$

$2000-3000$ $100$

$3000-4000$ $40$

$4000-5000$ $15$

$5000-6000$ $5$

Total $600$

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Calculate the mean of the frequency distribution of the marks scored by $100$ students in a mathematics test: Marks $0-10$ $10-20$ $20-30$ $30-40$ $40-50$ No. of students $20$ $10$ $20$ $30$ $20$