100 surnames were randomly picked up from a local telephone directory and a frequency distribution of the number of letters in the English alphabet in the surnames was found as follows:

(i) Draw a histogram to depict the given information.
(ii) Write the class interval in which the maximum number of surnames lie.

Solution:

1. It can be observed from the given data that it has class intervals of varying widths.
2. The proportion of the number of surnames per 2 letters (class interval of minimum class size for reference) can be made.

(i) The length of rectangles are calculated as below:

We will take the number of letters on the x-axis and the proportion of the number of surnames per every 2 letter interval on the y-axis.

We will choose an appropriate scale of 1 unit = 4 surnames for the  y-axis. The histogram can be constructed as follows:

(ii) The class interval in which the maximum number of surnames lie is 6 – 8.

☛ Check: NCERT Solutions for Class 9 Maths Chapter 14

Video Solution:

100 surnames were randomly picked up from a local telephone directory and a frequency distribution of the number of letters in the English alphabet in the surnames was found as follows: (i) Draw a histogram to depict the given information. (ii) Write the class interval in which the maximum number of surnames lie.

NCERT Solutions for Class 9 Maths Chapter 14 Exercise 14.3 Question 9

Summary:

The data of 100 surnames were randomly picked up from a local telephone directory is given. We have made a Histogram to represent the data. The class interval in which the maximum number of surnames lies 6 – 8.

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