
RS Aggarwal Solutions for Class 10 Maths Chapter 9 Exercise 9.6: RS Aggarwal Solutions for Class 10 Maths Chapter 9 Exercise 9.6 focus on cumulative frequency distribution and how to draw cumulative frequency curves, called ogives.
They help students learn how to plot and understand ogives step by step. By practicing these exercises, students can get better at analyzing and visualizing data, which is important for their math exams. These solutions are a great resource for understanding cumulative frequency and its uses in statistics.RS Aggarwal Solutions for Class 10 Maths Chapter 9 Exercise 9.6 PDF
Q. Which of the following is not a measure of central tendency?
(a) Mean (b) Mode (c) Median (d) RangeSolution: C
Mean and mode does not require construction of cumulative frequency, but median necessarily requires construction of cumulative frequency, unless it is raw data (in which median is the (n/2)th value, when there are n number of observations; and the average of (n/2)th and (n/2 + 1)th values, when there are n observations).Q. Which of the following cannot be determined graphically?
(a) Mean (b) Mode (c) Median (d) None of theseSolution: C
Given: mean = 27 and median = 33 We have to find the value of mode. Empirical relationship is given by, Mode = 3(Median) – 2(Mean) ⇒ Mode = 3(33) – 2(27) ⇒ Mode = 99 – 54 = 45Q. Which of the following measures of central tendency is influenced by extreme values?
(a) Mean (b) Mode (c) Median (d) None of theseSolution: B
Solution:
We prepare the cumulative frequency table, as shown:| Class | Frequency(f) | Cumulative frequency |
| 135-140 | 6 | 6 |
| 140-145 | 10 | 16 |
| 145-150 | 18 | 34 |
| 150-155 | 22 | 56 |
| 155-160 | 20 | 76 |
| 160-165 | 15 | 91 |
| 165-170 | 6 | 97 |
| 170-175 | 3 | 100 |
| N=Σf=100 |
Question:
The median of the following data is 16. Find the missing frequencies a and b if the total of frequencies is 70.
| Class | 0 − 5 | 5 − 10 | 10 − 15 | 15 − 20 | 20 − 25 | 25 − 30 | 30 − 35 | 35 − 40 |
| Frequency | 12 | a | 12 | 15 | b | 6 | 6 | 4 |
| Class | Frequency fi | Cumulative frequency |
| 0-5 | 12 | 12 |
| 5-10 | a | 12+a |
| 10-15 | 12 | 24+a |
| 15-20 | 15 | 39+a |
| 20-25 | b | 39+a+b |
| 25-30 | 6 | 45+a+b |
| 30-35 | 6 | 51+a+b |
| 35-40 | 4 | 55+a+b |
| Total | N=Σfi=70 |
| Literacy rate (%) | Number of cities (fi) | Class mark (xi) | (fixi) |
| 45 - 55 | 4 | 50 | 200 |
| 55 - 65 | 11 | 60 | 660 |
| 65 - 75 | 12 | 70 | 840 |
| 75 - 85 | 9 | 80 | 720 |
| 85 - 95 | 4 | 90 | 360 |
| Total | ∑fi=40 | ∑(fi×xi)=2780 |
Let us choose a = 25, h = 10,
then di = xi - 25
and
ui = (xi−25)/10
Using Step-deviation method, the given data is shown as follows:
| Class | Frequency (fi) | Class mark (xi) | di= xi- 25 | ui = (xi−25)/10 | fiui |
| 0 - 10 | 7 | 5 | -20 | -2 | -14 |
| 10 - 20 | 10 | 15 | -10 | -1 | -10 |
| 20 - 30 | 15 | 25 | 0 | 0 | 0 |
| 30 - 40 | 8 | 35 | 10 | 1 | 8 |
| 40 - 50 | 10 | 45 | 20 | 2 | 20 |
| Total | ∑fi=50 | ∑(fi×ui)=4 |
| Class | Frequency (fi) | Class mark (xi) | di= xi- 40 | ui = xi−40/10 | fiui |
| 5 - 15 | 6 | 10 | -30 | -3 | -18 |
| 15 - 25 | 10 | 20 | -20 | -2 | -20 |
| 25 - 35 | 16 | 30 | -10 | -1 | -16 |
| 35 - 45 | 15 | 40 | 0 | 0 | 0 |
| 45 - 55 | 24 | 50 | 10 | 1 | 24 |
| 55 - 65 | 8 | 60 | 20 | 2 | 16 |
| 65 - 75 | 7 | 70 | 30 | 3 | 21 |
| Total | ∑fi=86 | ∑(fi×ui)=7 |
| Class | Frequency (fi) | Class mark (xi) | di= xi- 40 | ui = xi−40/10 | fiui |
| 5 - 15 | 6 | 10 | -30 | -3 | -18 |
| 15 - 25 | 10 | 20 | -20 | -2 | -20 |
| 25 - 35 | 16 | 30 | -10 | -1 | -16 |
| 35 - 45 | 15 | 40 | 0 | 0 | 0 |
| 45 - 55 | 24 | 50 | 10 | 1 | 24 |
| 55 - 65 | 8 | 60 | 20 | 2 | 16 |
| 65 - 75 | 7 | 70 | 30 | 3 | 21 |
| Total | ∑fi=86 | ∑(fi×ui)=7 |
| Runs scored | 2500-3500 | 3500-4500 | 4500-5500 | 5500-6500 | 6500-7500 | 7500-8500 |
| Number of batsman | 5 | x | y | 12 | 6 | 2 |
Solution:
We prepare the cumulative frequency table, as shown:| Runs scored | No. of batsmen | Cumulative frequency |
| 2500-3500 | 5 | 5 |
| 3500-4500 | x | 5+x |
| 4500-5500 | y | 5+x+y |
| 5500-6500 | 12 | 17+x+y |
| 6500-7500 | 6 | 23+x+y |
| 7500-8500 | 2 | 25+x+y |
| Total | N=Σfi=60 |
| Marks | Frequency fi | C.F |
| 0-10 | 12 | 12 |
| 10-20 | 20 | 32 |
| 20-30 | 25 | 57 |
| 30-40 | 23 | 80 |
| 40-50 | 12 | 92 |
| 50-60 | 24 | 116 |
| 60-70 | 24 | 116 |
| 70-80 | 36 | 200 |
| N=∑fi=200 |
Solution:
We prepare the cumulative frequency table, as shown below:| Class | Frequency | Cumulative frequency |
| 0-10 | f1 | f1 |
| 10-20 | 5 | f1+5 |
| 20-30 | 9 | f1+14 |
| 30-40 | 12 | f1+26 |
| 40-50 | f2 | f1+f2+26 |
| 50-60 | 3 | f1+f2+29 |
| 60-70 | 2 | f1+f2+31 |
| N=Σf=40 |
Solution:
The correct answer is: (b) Both Assertion (A) and Reason (R) are true but Reason (R) is not a correct explanation of Assertion (A). Clearly, Reason (R) is true. But we got the value of mode thus: The maximum frequency is 23 and the modal class is 12-15. Using, M o d e = l + ( f 1 − f 0 2 f 1 − f 0 − f 2 ) ∗ h where l = lower limit of the modal class, h = size of the class interval (assuming all class sizes to be equal), f 1 = frequency of the modal class, f 0 = frequency of the class preceding the modal class, f 2 = frequency of the class succeeding the modal class. M o d e = 12 + ( 23 − 21 2 ∗ 23 − 21 − 10 ) ∗ 3 ⇒ M o d e = 12 + ( 2 15 ) ∗ 3 ⇒ M o d e = 12 + 0.4 ⇒ M o d e = 12.4 ∴ Assertion (A) and Reason (R) are true. However, Reason (R) isn't the correct explanation of Assertion (A). Q. The mean of 2, 7, 6 and x is 15 and the mean of 18, 1, 6, x and y is 10.What is the value of y? (a)5 (b)10 (c)20 (d)30