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Question
Why do we group data?
Solution
The data obtained in original form are called raw data. Raw data does not give any useful information and is rather confusing to mind. Data is grouped so that it becomes
understandable can be interpreted. According to various characteristics groups are formed
by us. After grouping the data, we are in position to make calculations of certain values which
will help us in describing and analyzing the data.
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RELATED QUESTIONS
Give five examples of data that you can collect from day to day life.
The monthly pocket money of six friends is given below: Rs. 45, Rs. 30, Rs. 40, Rs. 50, Rs.
25, Rs. 45.
(i) What is the highest pocket money?
(ii) What is the lowest pocket money?
(iii) What is the range?
(iv) Arrange the amounts of pocket money in ascending order.
Write the class-size in each of the following:
(i) 0 – 4, 5 – 9, 10 – 14
(ii) 10 – 19, 20 – 29, 30 – 39
(iii) 100 – 120, 120 – 140, 160 – 180
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The final marks in mathematics of 30 students are as follows:
53, 61, 48, 60, 78, 68, 55, 100,67,90
75,88,77,37,84,58,60,48,62,56
44, 58, 52, 64, 98, 59, 70, 39, 50, 60
(i) Arrange these marks in the ascending order, 30 to 39 one group, 40 to 49 second group etc.
Now answer the following:
(ii) What is the highest score?
(iii) What is the lowest score?
(iv) What is the range?
(v) If 40 is the pass mark how many have failed?
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The weights of new born babies (in kg) in a hospital on a particular day are as follows:
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(iii) Determine the lowest weight.
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The number of runs scored by a cricket. player in 25 innings are as follows:
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Tabulate the data and resent the data as a cumulative frequency table using 70-79 as one of the class intervals.
Classify following information as primary or secondary data.
The information of heights of students was gathered from school records and sent to the head office, as it was to be sent urgently.
Classify following information as primary or secondary data.
In the village Nandpur, the information collected from every house regarding students not attending school.
Classify following information as primary or secondary data.
For science project, information of trees gathered by visiting a forest.
