Calculate the mean deviation from the mean of the following distribution.

Marks	0-10	10-20	20-30	30-40	40-50
Numbers of students	5	8	15	16	6

4

(a)

Find the mean and standard deviation of the following frequency distribution

xi	6	10	14	18	24	28	30
fi	2	4	7	12	8	4	3

4

(a)

Find the mean and standard deviation for the following data.

Age(in years)	Number of teachers
25-30 30-35 35-40 40-45 45-50 50-55	30 23 20 14 10 3

4

(a)

Calculate the mean deviation from the median of the following data

Wages per week in Rs	10-20	20-30	30-40	40-50	50-60	60-70	70-80
No. of workers	4	6	10	20	10	6	4

4

(a)

Find the variance and standard deviation for the following data:
65, 68, 58, 44, 48, 45, 60, 62, 60, 50

4

(a)

Find the mean deviation about the mean for the data

Income per day	0-100	100-200	200-300	300-400	400-500	500-600	600-700	700-800
Number of persons	4	8	9	10	7	5	4	3

5

(a)

Find the mean deviation about the mean for the data

Height in cm	95-105	105-115	115-125	125-135	135-145	145-155
Number of boys	9	13	26	30	12	10

5

(a)

Find the mean and standard deviation of the following distribution:

Marks	20-30	30-40	40-50	50-60	60-70	70-80	80-90
Number of students	3	6	13	15	14	5	4

5

(a)

Find the mean and variance for each of the data :

xi	6	10	14	18	24	28	30
fi	2	4	7	12	8	4	3

5

(a)

From the prices of shares X and Y below, find out which is more stable in value:

X	35	54	52	53	56	58	52	50	51	49
Y	108	107	105	105	106	107	104	103	104	101

5

(a)

The mean and variance of eight observations are 9 and 9.25 respectively. If six of the observations are 6, 7, 10, 12, 12 and 13, find the remaining two observations.

5

(a)