# NCERT Class 9 Solutions: Statistics (Chapter 14) Exercise 14.3-Part 3 (For CBSE, ICSE, IAS, NET, NRA 2022)

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Q-7 The runs scored by two teams A and B on the first 60 balls in a cricket match are given below:

 Number of balls Teams A Team B 2 5 1 6 8 2 9 10 4 5 5 6 6 3 10 4 6 8 2 10

Represent the table data of both the teams on the same graph by frequency polygons.

[Hint: First make the class intervals continuous.]

Solution:

Convert to continuous frequency distribution:

Difference between lower limit of class and upper limit of preceding class:

Hence, added to each upper class limit and subtract from the lower class limits.

Class marks

Obtain distribution is given as under:

 Number of balls Class marks Team A Team B 3.5 2 5 9.5 1 6 15.5 8 2 21.5 9 10 27.5 4 5 33.5 4 5 39.5 6 3 45.5 10 4 51.5 6 8 57.5 2 10

Class mark on x-axis and number of balls on y-axis

Drawn the graph:

Q-8 A random survey of the number of children of various age groups playing in park was found as follows:

 Age (in years) Number of children 5 3 6 12 9 10 4

Draw a histogram to represent the data above.

Solution:

As given frequency data in class size are different.

So, we calculate adjusted frequency for each class using formula: