RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14D

RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14D

These Solutions are part of RS Aggarwal Solutions Class 9. Here we have given RS Aggarwal Solutions Class 9 Chapter 14 Statistics Ex 14D.

Other Exercises

Question 1.
Solution:
(i) First eight natural numbers are 1, 2, 3, 4, 5, 6, 7, 8
∴ Mean = \(\frac { 1+2+3+4+5+6+7+8 }{ 8 } \) = \(\frac { 36 }{ 8 } \) = \(\frac { 9 }{ 2 } \) = 4.5
(ii) First ten odd numbers are 1, 3, 5, 7, 9, 11, 13, 15, 17, 19
∴ Mean = \(\frac { 1+3+5+7+9+11+13+15+17+179 }{ 10 } \) = \(\frac { 100 }{ 10 } \) = 10
(iii) First five prime numbers are 2, 3, 5, 7, 11.
∴ Mean = \(\frac { 2+3+5+7+11 }{ 5 } \) = \(\frac { 28 }{ 5 } \) = 5.6
(iv) First six even numbers are 2, 4, 6, 8, 10, 12
∴ Mean = \(\frac { 2+4+6+8+10+12 }{ 10 } \) = \(\frac { 42 }{ 6 } \) = 7
(v) First seven multiples of 5 are 5, 10, 15, 20, 25, 30, 35
∴ Mean = \(\frac { 5+10+15+20+25+30+35 }{ 7 } \) = \(\frac { 140 }{ 7 } \) = 20
(vi) All the factors of 20 are, 1, 2, 4, 5, 10, 20
∴ Mean = \(\frac { 1+2+4+5+10+20 }{ 6 } \) = \(\frac { 42 }{ 6 } \) = 7

Question 2.
Solution:
No. of families (n) = 10
Sum of children (∑x1) = 2 + 4 + 3 + 4 + 2 + 0 + 3 + 5 + 1 + 6 = 30
∴ Mean \(\left( \overline { x } \right) =\frac { \sum { x1 } }{ n } =\frac { 30 }{ 10 } =3\)

Question 3.
Solution:
Here number of days (n) = 7
Number of books (∑x1) = 105 + 216 + 322 + 167 + 273 + 405 + 346 = 1834
∴ Mean \(\left( \overline { x } \right) =\frac { \sum { x1 } }{ n } =\frac { 1864 }{ 7 } =262 books\)

Question 4.
Solution:
Number of days (n) = 6
Sum of temperature (∑x) = 35.5 + 30.8 + 27.3 + 32.1 + 23.8 + 29.9 = 179.4°F
∴ Mean temperature = \(\frac { \sum { x } }{ n } =\frac { 179.4 }{ 6 } \)=29.9°F

Question 5.
Solution:
Number of students (n) = 12
Sum of marks (∑x) = 64 + 36 + 47 + 23 + 0 + 19 + 81 + 93 + 72 + 35 + 3 + 1 = 474
= \(\frac { \sum { x1 } }{ n } =\frac { 474 }{ 12 } \) = 39.5

Question 6.
Solution:
Here, n = 6
and arithmetic mean =13
Total sum = 13 x 6 = 78.
But sum of 7 + 9+ 11 + 13 + 21=61
Value of x = 78 – 61 = 17
Hence x = 17 Ans.

Question 7.
Solution:
Let x1, x2, x3, … x24 be the 24 numbers
\(\frac { x1+x2+x3+…..+x24 }{ 24 } =35\)
=> x1 + x2 + x3 +….+ x24 = 35 x 24
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14D Q7.1

Question 8.
Solution:
Let x1 + x2 + x3……..x20 be the 20 numbers
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14D Q8.1

Question 9.
Solution:
Let x1, x2, x3 … x15 be the numbers
Mean = \(\frac { x1+x2+x3+…..+x15 }{ 15 } = 27\)
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14D Q9.1

Question 10.
Solution:
Let x1, x2, x3 … x12 be the numbers
Mean = \(\frac { x1+x2+x3+…..+x12 }{ 12 }\) = 40
=> x1+x2+x3+….+x12 = 40 X 12 =480
Now,new numbers are \(\frac { x1 }{ 8 } ,\frac { x2 }{ 8 } ,\frac { x3 }{ 8 } ,..\frac { x12 }{ 8 } \)
Mean = \(\frac { \frac { x1 }{ 8 } +\frac { x2 }{ 8 } +\frac { x3 }{ 8 } +…..+\frac { x12 }{ 8 } }{ 12 } \)
= \(\frac { 1 }{ 8 } \frac { \left( x1+x2+x3+….x12 \right) }{ 12 } \)
= \(\frac { 480 }{ 8X12 } \) = 5
Mean of new numbers =5

Question 11.
Solution:
Let x1, x2, x3,…..x20 are the numbers
Mean = \(\frac { x1+x2+x3+…x20 }{ 20 }\) = 18
=> x1 + x2 + x3 +….+ x20 = 18 X 20 =360
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14D Q11.1

Question 12.
Solution:
Mean weight of 6 boys = 48 kg
Their total weight = 48 x 6 = 288 kg
Weights of 5 boys among them, are 51 kg, 45 kg, 49 kg, 46 kg and 44 kg
Sum of weight of 5 boys = (51 + 45 + 49 + 46 + 44) kg = 235 kg
Weight of 6th boy = 288 kg – 235 kg = 53 kg Ans.

Question 13.
Solution:
Mean of 50 students = 39
Total score = 39 x 50 = 1950
Now correct sum of scores = 1950 – Wrong item + Correct item= 1950 – 23 + 43
= 1950 + 20 = 1970
Correct mean = \(\frac { 1970 }{ 50 } \) = 39.4 Ans.

Question 14.
Solution:
Mean of 100 items = 64
The sum of 100 items = 64 x 100 = 6400
New sum of 100 items = 6400 + 36 + 90 – 26 – 9 = 6526 – 35 = 6491,
Correct mean = \(\frac { 6491 }{ 100 }\) =64.91 = 64.91 Ans.

Question 15.
Solution:
Mean of 6 numbers = 23
Sum of 6 numbers = 23 x 6 = 138
Excluding one number, the mean of remaining 5 numbers = 20
Total of 5 numbers = 20 x 5 = 100
Excluded number = 138 – 100 = 38 Ans.

Hope given RS Aggarwal Solutions Class 9 Chapter 14 Statistics Ex 14D are helpful to complete your math homework.

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RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14C

RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14C

These Solutions are part of RS Aggarwal Solutions Class 9. Here we have given RS Aggarwal Solutions Class 9 Chapter 14 Statistics Ex 14C.

Other Exercises

Question 1.
Solution:
It is clear that the given frequency distribution is in exclusive form, we represent the daily wages (in rupees) along x-axis and no. of workers along y-axis. Then we construct rectangles with class intervals as bases and corresponding frequencies as heights as shown given below:
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14C Q1.1

Question 2.
Solution:
We shall take daily earnings along x-axis and number of stores along y-axis. Then we construct rectangles with the given class intervals as bases and corresponding frequency as height as shown in the graph.
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14C Q2.1

Question 3.
Solution:
We shall take heights along x-axis and number of students along y-axis. Then we shall complete the rectangles with the given class intervals as bases and frequency as height and complete the histogram as shown below :
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14C Q3.1

Question 4.
Solution:
We shall take class intervals along x-axis and frequency along y-axis Then we shall complete the rectangles with given class interval as bases and frequency as heights and complete the histogram as shown below.
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14C Q4.1

Question 5.
Solution:
The given frequency distribution is in inclusive form first we convert it into exclusive form at given below.
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14C Q5.1
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14C Q5.2
Now, we shall take class intervals along x-axis and frequency along y-axis and draw rectangles with class intervals as bases and frequency as heights and complete the histogram as shown.

Question 6.
Solution:
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14C Q6.1

Question 7.
Solution:
In the given distribution class intervals are different size. So, we shall calculate the adjusted frequency for each class. Here minimum class size is 4. We know that adjusted
frequency of the class is \(\frac { max\quad class\quad size }{ class\quad size\quad of\quad this\quad class } \)  x its frequency
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14C Q7.1
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14C Q7.2

Question 8.
Solution:
We shall take two imagined classes one 0-10 at the beginning with zero frequency a id other 70-80 at the end with zero frequency.
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14C Q8.1
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14C Q8.2
Now, plot the points” (5, 0), (15, 2), (25, 5), (35, 12), (45, 19), (55, 9), (65, 4), (75, 0) on the graph and join them its order to get a polygon as shown below.

Question 9.
Solution:
We take Age (in years) along x-axis and number of patients along y-axis. First we complete the histogram and them join the midpoints of their tops in order
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14C Q9.1
We also take two imagined classes. One 0-10 at the beginning and other 70-80 at the end and also join their midpoints to complete the polygon as shown.

Question 10.
Solution:
We take class intervals along x-axis and frequency along y-axis.
First we complete the histogram and then join the midpoints of the tops of adjacent rectangles in order. We shall take two imagined classes 15-20 at the beginning and 50-55 at the end.
We also join their midpoints to complete the polygon as shown
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14C Q10.1

Question 11.
Solution:
We represent class interval on x-axis and frequency on y-axis. First we construct the histogram and then join the midpoints of the tops of each rectangle by line segments. We shall take two imagined class i.e. 560-600 at the beginning and 840-900 at the end. Join their midpoints also to complete
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14C Q11.1

Question 12.
Solution:
We will take the imagined class 11-0 at the beginning and 61-70 at the end. Each with frequency zero. Thus, we have,
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14C Q12.1
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14C Q12.2
Now we will mark the points A (-5.5, 0), B(5.5, 8), C(15.5, 3) D(25.5, 6), E(35.5, 12), F(45.5, 2), G(55.5, 7) and H(65.5, 0) on the graph and join them in order to get the required frequency polygon.

Hope given RS Aggarwal Solutions Class 9 Chapter 14 Statistics Ex 14C are helpful to complete your math homework.

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RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14B

RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14B

These Solutions are part of RS Aggarwal Solutions Class 9. Here we have given RS Aggarwal Solutions Class 9 Chapter 14 Statistics Ex 14B.

Other Exercises

Question 1.
Solution:
We shall take the game along x-axis and number of students along y-axis.
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14B Q1.1

Question 2.
Solution:
We shall take the time on x-axis and temperature (in °C) on y-axis.
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14B Q2.1

Question 3.
Solution:
We shall take name of vehicle on x-axis and velocity (in km/hr) on y-axis
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14B Q3.1

Question 4.
Solution:
We shall take sports on x-axis and number of students on y-axis.
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14B Q4.1

Question 5.
Solution:
We shall take years on x-axis and number of students on y-axis.
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14B Q5.1

Question 6.
Solution:
We shall take years on x-axis and number of students on y-axis.
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14B Q6.1

Question 7.
Solution:
We shall take years on x-axis and number of students on y-axis.
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14B Q7.1

Question 8.
Solution:
We shall take years on x-axis and number of students on y-axis.
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14B Q8.1

Question 9.
Solution:
We shall take years on x-axis and number of students on y-axis.
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14B Q9.1

Question 10.
Solution:
We shall take years on x-axis and number of students on y-axis.
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14B Q10.1

Question 11.
Solution:
We shall take week on x-axis and Rate per 10g (in Rs.) on y-axis.
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14B Q11.1

Question 12.
Solution:
We shall take mode of transport on x-axis and number of students on y-axis.
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14B Q12.1

Question 13.
Solution:
We see from the graph that
(i) It shows the marks obtained by a student in various subjects.
(ii) The student is very well in mathematics.
(iii) The student is very’ poor, in Hindi.
(iv) Average marks
= \(\frac { 60+35+75+50+60 }{ 5 } \) (Here x = 5)
= \(\frac { 280 }{ 5 } \)
= 56 marks
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14B Q13.1

Hope given RS Aggarwal Solutions Class 9 Chapter 14 Statistics Ex 14B are helpful to complete your math homework.

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RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14A

RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14A

These Solutions are part of RS Aggarwal Solutions Class 9. Here we have given RS Aggarwal Solutions Class 9 Chapter 14 Statistics Ex 14A.

Other Exercises

Question 1.
Solution:
Statistics is a science which deals with the collection, presentation, analysis and interpretations of numerical data.

Question 2.
Solution:
(i) Numerical facts alone constitute data
(ii) Qualitative characteristics like intelligence, poverty etc. which cannot be measured, numerically, don’t form data.
(iii) Data are an aggregate of facts. A single observation does not form data.
(iv) Data collected for a definite purpose may not be suited for another purpose.
(v) Data is different experiments are comparable.

Question 3.
Solution:
(i) Primary data : The data collected by the investigator himself with a definite plan in mind are called primary data.
(ii) Secondary data : The data collected by some one other than the investigator are called secondary data. The primary data is more reliable and relevant.

Question 4.
Solution:
(i) Variate : Any character which is capable of taking several different values is called a variate or variable.
(ii) Class interval : Each group into which the raw data is condensed, is called a class interval
(iii) Class size : The difference between the true upper limit and the true lower limit of a class is called class size.
(iv) Class Mark : \(\frac { upper\quad limit+lower\quad limit }{ 2 } \) is called a class mark
(v) Class limits : Each class is bounded by two figures which are called class limits which are lower class limit and upper class limit.
(vi) True class limits : In exclusive form, the upper and lower limits of a class are respectively are the true upper limit and true lower limit but in inclusive form, the true lower limit of a class is obtained by subtracting O.S from lower limit of the class and for true limit, adding 0.5 to the upper limit.
(vii) Frequency of a class : The number of times an observation occurs in a class is called its frequency.
(viii) Cumulative frequency of a class : The cumulative frequency corresponding to a class is the sum of all frequencies upto and including that class.

Question 5.
Solution:
The given data can be represent in form of frequency table as given below:
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14A Q5.1

Question 6.
Solution:
The frequency distribution table of the given data is given below :
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14A Q6.1

Question 7.
Solution:
The frequency distribution table of the
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14A Q7.1

Question 8.
Solution:
The frequency table is given below :
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14A Q8.1

Question 9.
Solution:
The frequency table of given data is given below :
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14A Q9.1

Question 10.
Solution:
The frequency distribution table of the given data in given below :
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14A Q10.1

Question 11.
Solution:
The frequency table of the given data:
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14A Q11.1

Question 12.
Solution:
The cumulative frequency of the given table is given below:
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14A Q12.1

Question 13.
Solution:
The given table can be represented in a group frequency table in given below :
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14A Q13.1

Question 14.
Solution:
Frequency table of the given cumulative frequency is given below :
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14A Q14.1

Question 15.
Solution:
A frequency table of the given cumulative frequency table is given below :
RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14A Q15.1

 

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RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D

RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D

These Solutions are part of RS Aggarwal Solutions Class 9. Here we have given RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D.

Other Exercises

Question 1.
Solution:
(i) Radius of sphere = 3.5cm
(a) Volume = \(\frac { 4 }{ 3 } \) πr3
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q1.1
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q1.2

Question 2.
Solution:
Let r be the radius of the sphere and volume = 38808 cm3
∴\(\frac { 4 }{ 3 } \) πr3 = 38803
=> \(\frac { 4 }{ 3 } \) x \(\frac { 22 }{ 7 } \) r3 = 38803
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q2.1

Question 3.
Solution:
Let r be the radius of the sphere
∴ Volume = \(\frac { 4 }{ 3 } \) πr3
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q3.1

Question 4.
Solution:
Surface area of a sphere = 394.24 m2
Let r be the radius, then 4πr2 = 394.24
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q4.1

Question 5.
Solution:
Surface area of sphere = 576π cm2
Let r be the radius, then 4r2 = 576π
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q5.1

Question 6.
Solution:
Outer diameter of shell = 12cm,
Outer radius (R) = \(\frac { 12 }{ 2 } \) = 6cm
and inner diameter = 8cm
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q6.1
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q6.2

Question 7.
Solution:
Length of cuboid of (l) = 12cm
Breadth (b) = 11cm
and height (h) = 9cm
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q7.1
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q7.2

Question 8.
Solution:
Radius of sphere (r) = 8cm
Volume = \(\frac { 4 }{ 3 } \)πr3
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q8.1
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q8.2

Question 9.
Solution:
Radius of solid sphere (R) = 3cm.
Volume = \(\frac { 4 }{ 3 } \)π(R)3 = \(\frac { 4 }{ 3 } \)π(3)3 cm3
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q9.1
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q9.2

Question 10.
Solution:
Radius of metallic sphere (R) = 10.5cm
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q10.1

Question 11.
Solution:
Diameter of a cylinder = 8cm
Radius (r) = \(\frac { 8 }{ 2 } \) = 4cm
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q11.1

Question 12.
Solution:
Diameter of sphere = 6cm
Radius (R) = \(\frac { 6 }{ 2 } \) = 3cm
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q12.1

Question 13.
Solution:
Diameter of sphere = 18cm
Radius (R) = \(\frac { 18 }{ 2 } \) = 9cm.
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q13.1

Question 14.
Solution:
Diameter of the sphere = 15.6 cm
Radius (R) = \(\frac { 15.6 }{ 2 } \) = 7.8 cm
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q14.1
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q14.2

Question 15.
Solution:
Diameter of the canonball = 28cm
Radius (R) = \(\frac { 28 }{ 2 } \) = 14 cm
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q15.1
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q15.2

Question 16.
Solution:
Given,
Radius of spherical big ball (R) = 3cm
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q16.1
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q16.2

Question 17.
Solution:
Ratio in the radii of two spheres = 1:2
Let radius of smaller sphere = r then,
radius of bigger sphere = 2r
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q17.1

Question 18.
Solution:
Let r1 and r2 be the radii of two spheres
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q18.1

Question 19.
Solution:
Radius of the cylindrical tub = 12cm.
First level of water = 20cm
Raised water level = 6.75cm.
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q19.1

Question 20.
Solution:
Radius of the ball (r) = 9cm.
Volume of ball = \(\frac { 4 }{ 3 } \)πr³
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q20.1

Question 21.
Solution:
Given,
Radius of hemisphere of lead (r) = 9cm.
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q21.1
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q21.2

Question 22.
Solution:
Given,
Radius of hemispherical bowl (r) = 9cm
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q22.1
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q22.2

Question 23.
Solution:
External radius of spherical shell (R) = 9cm
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q23.1
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q23.2

Question 24.
Solution:
Inner radius (r) = 4 cm
Thickness of steel used = 0.5
RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D Q24.1

Hope given RS Aggarwal Class 9 Solutions Chapter 13 Volume and Surface Area Ex 13D are helpful to complete your math homework.

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