# Chapter 15 Statistics Ex – 15.1

Find the mean deviation about the mean for the data in Exercises 1 and 2.

Question 1.

4, 7, 8, 9, 10, 12, 13, 17

Solution:

Mean of the given data is

Question 2.

38, 70, 48, 40, 42, 55, 63, 46, 54, 44

Solution:

Mean of the given data is

Question 3.

13, 17, 16, 14, 11, 13, 10, 16, 11, 18, 12, 17

Solution:

Arranging the data in ascending order, we have
10, 11, 11, 12, 13, 13, 14, 16, 16, 17, 17, 18
Here n = 12 (which is even)
So median is the average of 6th and 7th observations

Question 4.

36, 72, 46, 42, 60, 45, 53, 46, 51, 49

Solution:

Arranging the data in ascending order, we have 36, 42, 45, 46, 46, 49, 51, 53, 60, 72
Here n = 10 (which is even)
So median is the average of 5th and 6th observations

Find the mean deviation about the mean for the data in Exercises 5 and 6.

Question 5.

Solution:

Question 6.

Solution:

Find the mean deviation about the median for the data in Exercises 7 and 8.

Question 7.

Solution:

Question 8.

Solution:

Find the mean deviation about the mean for the data in Exercises 9 and 10.

Question 9.

Solution:

Question 10.

Solution:

Question 11.

Find the mean deviation about median for the following data:

Solution:

Question 12.

Calculate the mean deviation about median age for the age distribution of 100 persons given below:

[Hint: Convert the given data into continuous frequency distribution by subtracting 0.5 from the lower limit and adding 0.5 to the upper limit of each class interval]

Solution: