Unit-15 Handling Data

In this unit you will learn about need of data collection, grouping of data, graphical representation of data and data analysis.

Submit your question

Give one example each of the situation that would yield i) discrete data ii) continuous data?

The number of workers on duty each day in a factory are grouped into a distribution having the classes 20-34, 35-49, 50-64, 65-79 and 80-94. Find

a) the class width

b) the class limits

c) the class marks

Represent the following data showing infant mortality in different cities by a pie diagram?

At a newspaper office, the time required to set the entire front page in type was recorded for 50 days. The data, to the nearest tenth of a minute, are given below.

20.8 22.8 21.9 22.0 20.7 20.9 25.0 22.2 22.8 20.1

25.3 20.7 22.5 21.2 23.8 23.3 20.9 22.9 23.5 19.5

23.7 20.3 23.6 19.0 25.1 25.0 19.5 24.1 24.2 21.8

21.3 21.5 23.1 19.9 24.2 24.1 19.8 23.9 22.8 23.9

19.7 24.2 23.8 20.7 23.8 24.3 21.1 20.9 21.6 22.7

a) Construct a frequency distribution and a ”less than”’ cumulative frequency distribution from the data using intervals of 0.8 minute.

b) Construct a frequency polygon from the data.

c) Construct a “less than” frequency ogive from the data.

Find the mean of the data:

i) 3,5,2,6,5,9,5,2,8,6

ii) 516, 487, 503, 495, 489.

The height X (in cm.) of 40 men intending to join Army is given below

138 164 150 132 144 125 149 157

146 158 140 147 136 148 152 144

168 126 138 176 163 118 154 165

146 173 142 147 135 153 140 135

161 145 135 142 150 156 145 128

Answer the following questions on the basis of the data given above

Is the variable X = Height of a man, discrete or continuous? What is the 40 minimum and maximum height?
Using the classes 118 − 123, 124 − 129, 130 − 135, . . . draw up the frequency distribution of X.
How many men are taller than 159 cm.?
How many men are of height between 136 to 159 cm.?

The following data give the marks obtained by 80 students in a test. Form a grouped frequency table with appropriate number of classes.

68 84 75 82 68 90 62 88 76 93

73 79 88 73 60 93 71 59 85 75

61 65 75 87 74 62 95 78 63 72

66 78 80 75 94 77 69 74 68 60

96 78 89 60 75 95 60 79 83 71

79 62 67 97 78 85 76 65 71 75

65 80 73 57 88 78 62 76 53 74

86 67 73 80 72 63 76 75 85 77

The mean marks in Statistics of 50 students in a class was 72, and that of the 35 boys 75. Find the mean marks of girls in the class?

Find the median from the following frequency distribution?

For each of 18 chemical firms, the ratio of current assets to current liabilities is:

1.14 1.33 1.04 1.51 1.68 1.72 2.04 1.34 1.77

1.21 1.46 1.85 1.73 1.46 1.77 1.83 1.86 1.56

Determine the mean and median ratios of current assets to current liabilities of these firms?

Find the mean, median and mode of the following data:

The administrator of Apollo hospital conducted a survey of the number of days patients stayed in the hospital following an operation. The data are as given below.