

RS Aggarwal Solutions for Class 10 Maths Chapter 9 Exercise 9.1: In RS Aggarwal Solutions for Class 10 Maths Chapter 9 Exercise 9.1, Mean, Median, Mode of Grouped Data, students learn to calculate statistical measures for grouped data sets.
The chapter covers methods to find the mean, median, and mode when data is presented in grouped frequency distributions. It emphasizes understanding the concepts of central tendency and how to interpret them in real-world contexts. Through comprehensive exercises, students practice applying these formulas and interpreting results, enhancing their ability to analyze data effectively.RS Aggarwal Solutions for Class 10 Maths Chapter 9 Exercise 9.1 PDF
Q. If the mean of 5 observations x , x + 2 , x + 4 , x + 6 and x + 8 is 11 , find the value of x .
Q. If the mean of 25 observations is 27 and each observation is decreased by 7, what will be the new mean?
For equal class intervals, we will solve by finding mid points of these classes using direct method.
⇒ x̅ =
1150
40
⇒ x̅ = 28.75
Thus, mean is 28.75
∵ mean is given by
x̅ =
∑ fi ixi
∑ fi i
⇒ x̅ =
1980
40
⇒ x̅ = 49.5
Thus, mean is 49.5
We have got
Σfi = 50 & Σfixi = 13200
∵ mean is given by
x̅ =
∑ fi ixi
∑ fi i
⇒ x̅ =
13200
50
⇒ x̅ = 264
Thus, mean is 264
For equal class intervals, we will solve by finding mid points of these classes using direct method.
⇒ 24 =
270 + 25p
12 + p
⇒ 288 + 24p = 270 + 25p
⇒ 25p – 24p = 288 – 270
⇒ p = 18
Thus, p is 18
⇒ p = 11
Thus, p is 11.
⇒ x = 12
Substitute x = 12 in equation (ii),
12 + y = 37
⇒ y = 37 – 12
⇒ y = 25
Thus, x = 12 and y = 25.
