The following table shows the number of students and the time they utilized daily for their studies. Find the mean time spent by students for their studies by direct method.

Time (hrs.) 0 - 2 2 - 4 4 - 6 6 - 8 8 - 10

No. of students 7 18 12 10 3

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Solution

Class
(Time in hours) Class Mark
x_i Frequency
(Number of students)
f_i Class mark × Frequency
x_if_i

0 - 2 1 7 7

2 - 4 3 18 54

4 - 6 5 12 60

6 - 8 7 10 70

8 - 10 9 3 27

$\sum_{} f_{i} = 50$ $\sum_{} x_{i} f_{i} = 218$

Mean = $\frac{\sum_{} x_{i} f_{i}}{\sum_{} f_{i}}$
$= \frac{218}{50}$
= 4.36 hours
Hence, the mean time spent by students for their studies is 4.36 hours.

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Time (hrs.)	0 - 2	2 - 4	4 - 6	6 - 8	8 - 10
No. of students	7	18	12	10	3

Class (Time in hours)	Class Mark x_i	Frequency (Number of students) f_i	Class mark × Frequency x_if_i
0 - 2	1	7	7
2 - 4	3	18	54
4 - 6	5	12	60
6 - 8	7	10	70
8 - 10	9	3	27
		$\sum_{} f_{i} = 50$	$\sum_{} x_{i} f_{i} = 218$

The following table shows the number of students and the time they utilized daily for their studies. Find the mean time spent by students for their studies by direct method. Time (hrs.) 0 - 2 2 - 4 4 - 6 6 - 8 8 - 10 No. of students 7 18 12 10 3

The following table shows the number of students and the time they utilized daily for their studies. Find the mean time spent by students for their studies by direct method.

Time (hrs.) 0 - 2 2 - 4 4 - 6 6 - 8 8 - 10

No. of students 7 18 12 10 3