Find the mean deviation about the median for the data :
36, 72, 46, 42, 60, 45, 53, 46, 51, 49

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 deviation about median for the following data:

Marks	0-10	10 - 20	20 - 30	30 - 40	40 - 50	50 - 60
Number of Girls	6	8	14	16	4	2

5

(a)

Calculate the mean deviation about median age for the age distribution of 100 persons gives below:

Age	16-20	21-25	26-30	31-35	36-40	41-45	46-50	51-55
Number	5	6	12	14	26	12	16	9

[Hint Convert the given data into continuous frequency distribution by subtracting 0.5 from the lower limit and adding 0.5 to the upper limit of each class interval]

 

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)

Find the mean and variance for each of the data : 

xi	92	93	97	98	102	104	109
fi	3	2	3	2	6	3	3

5

(a)

Find the C.V of the following data:

Size (in m)	10-15	15-20	20-25	25-30	30-35	35-40
No.of items	2	8	20	35	20	15

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)

The mean and standard deviation of 20 observation are found to be 10 and 2 respectively. On rechecking, it was found that an observation 8 was incorrect. Calculate the correct mean and standard deviation in each of the following cases:
(i) If wrong item is omitted
(ii) If it is replaced by 12.

5

(a)

The mean and standard deviation of marks obtained by 50 students of a class in three subjects, Mathematics, physics and chemistry are given below:

Subject	Mathematics	Physics	Chemistry
Mean	42	32	40.9
Standard deviation	12	15	20

Which of the three subjects shows the highest variability in marks and which shows the lowest?

5

(a)