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Example 2: The number of goals scored by a hockey team in last 30 matches are shown below:

0 2 3 1 0 3 4 0 1 3

2 0 3 1 3 3 2 1 2 2
Draw a frequency distribution table for the given data. Also, answer the following questions.

(a) Find the number of matches in which the team scored 0 goals.
(b) Find the number of matches in which the team scored more than 3 goals.

Solution: The frequency distribution table for the given data is as follows:

Goals Tally Marks Frequency
0 4
1 4
2 5

3 6
4 1
Total 20

From the above frequency distribution table, it is clear that:
(a) In 4 matches, the hockey team scored 0 goals.
(b) The hockey team scored more than 3 goals in one match only.

Range of Data

Suppose the marks (out of 100) obtained in a mathematics test by the 20 students are
87, 50, 34, 78, 58, 78, 55, 87, 78, 94, 90, 92, 75, 90, 55, 84, 75, 64, 80, 98
Here, the highest marks obtained is 98 and lowest marks obtained is 34.
Difference between the highest marks and the lowest marks obtained is 98 – 34 = 64

It is called the range of the data.
Thus, the range is the difference between the highest and the lowest observations.

Example 3: The ages (in years) of 10 members of a joint family are as follows:
27, 47, 18, 4, 65, 26, 13, 83, 31, 37
(a) What is the age of the oldest family member? Quick Check

(b) What is the age of the youngest family member? How many members are
(c) What is the range of the ages of the family members? there in your family? Collect

Solution: Arranging the ages of the family members in ascending the data of the weight of
the family members.
order: 4, 13, 18, 26, 27, 31, 37, 47, 65, 83
What is range of the weight
(a) The age of oldest family member is 83 years. of your family?
(b) The age of youngest family member is 4 years.

(c) The range of the ages of family members
= Age of oldest family member – age of youngest family member
= 83 years – 4 years = 79 years

309 Data Handling