NCERT Solutions Class 10 Maths Exercise 12.1 of Chapter 12-Areas related to circles - Future Study Point

NCERT Solutions Class 10 Maths Exercise 12.1 of Chapter 12-Areas related to circles

class 10 maths ex.12.1

NCERT Solutions Class 10 Maths Exercise 12.1 -Areas related to circles

NCERT Solutions Class 10 Maths Exercise 12.1 of Chapter 12-Areas related to circles are the solutions of unsolved questions of NCERT maths text book of class 10 prescribed by CBSE. All NCERT solutions of unsolved questions are created by an expert of future study point. You can study here sample papers, solutions of previous year question papers, tips for the preparation of government entrance exams, and carrier in online jobs.

Click for online shopping

Future Study Point.Deal: Cloths, Laptops, Computers, Mobiles, Shoes etc

Download pdf of NCERT Solutions of class 10 maths chapter 12-Areas related to circles

Pdf-NCERT solutions of class 10 maths chapter 12-Areas related to Circle

NCERT Solutions for Class 10 Maths   Chapter 12-Areas related to circles

Exercise 12.1- Area Related to Circle

Exercise 12.2- Areas related to Circle

Exercise 12.3-Areas Related to the Circle

 

class 10 maths ex.12.1

 

Q1. The radii of the two circles 19 cm and 9 cm respectively . Find the radius of the circles which has a circumference equal to the sum of the circumferences of two circles.

Ans.  Circumference of the circle = 2πr, where r is the radius of the circle and π= 22/7

In the question, we are given the radii of two circles r1 = 19cm ,r2 = 9 cm

Let the radius of the required circle = R

According to question

Circumference of the required circle = Sum of the circumferences of two circles.

2πR = 2πr1+ 2πr2

2πR = 2π(r1 + r2)

R = 19 + 9 = 28

Therefore the radius of the circle is = 28 cm

Q2.The radii of the two circles 8 cm and 6 cm respectively. Find the radius of the circle having an area equal to the sum of the areas of two circles.

Ans.

Area of the circle = πr², where r is the radius of the circle and π= 22/7

In the question, we are given the radii of two circles r1 = 8cm ,r2 = 6cm

Let the radius of the required circle = R

According to question

Area of the required circle = Sum of the areas of two circles.

πR² = πr1²+ πr2²

πR² = π(r1² + r2²)

R²= 8² + 6²= 64+ 36 = 100

R = 10

Therefore the radius of the circle is = 10 cm

Q3. The given figure depicts an archery target with its 5 scoring areas from the centre outwards as Gold, Red, Blue, Black, and White. The diameter representing the Gold score is 21 cm and each of the other bands is 10.5 cm wide. Find the area of each of the five scoring regions.(Use π = 22/7).

Q3 exercise 12.1 class 9 maths

 

 

 

 

 

 

Ans. We are given the diameter of circle representing gold region = 21 cm

The radius of gold region is = 21/2 = 10.5 cm

Width of each band of colour is = 10.5 cm

Area of gold region =are of 1 st circle = πr² = (22/7)×10.5 ×10.5 = 346.5 sq.cm

Area of red band = Area of 2 nd circle  – Area of 1 st circle

= π[(radius of 2 nd circle)²- (radius of 1 st circle)²]

=22/7[(10.5 +10.5)²- (10.5)²]

22/7[ 21² -(10.5)²]

22/7[ 441 – 110.25]

22/7(330.75) = 22×47.25= 1039.5 sq.cm

Area of blue band = Area of 3 rd circle  – Area of 2 nd  circle

= π[(radius of 3 rd circle)²- (radius of 2 nd circle)²]

=22/7[(21+10.5)²- (21)²]

22/7[ 31.5² -(21)²]

22/7[ 992.25 – 441]

22/7(551.25) = 22×78.75= 1732.5 sq.cm

Area of black band = Area of 5 th circle  – Area of 3 rd  circle

= π[(radius of 4 th circle)²- (radius of 3 rd circle)²]

=22/7[(31.5+10.5)²- (31.5)²]

22/7[ 42² -(31.5)²]

22/7[  1764 – 992.25]

22/7(771.75) = 22×110.25= 2425.5 sq.cm

Area of white band = Area of 5 th circle  – Area of 4 th circle

= π[(radius of 5 th circle)²- (radius of 4 th circle)²]

=22/7[(42+10.5)²- (42)²]

22/7[( 52.5)² -(42)²]

22/7[  2756.25 – 1764]

22/7(992.25) = 22×141.75= 3118.5 sq.cm

Q4. The wheels of a car of diameter 80 cm each . How many complete revolutions does each wheel make in 10 minutes when the car is travelling at the speed of 66 km/h.

Ans. We are given the diameter of the wheel = 80 cm

The radius of the wheel,r = 80/2 = 40 cm

One revolution of the wheels corresponds to the distance traveled by the car= Circumference of the wheel = 2πr = (2×22/7 )40 = 1760/7 cm

The speed of car is given = 66 km/h means the car travels 66 km in 1 h

1h = 60 minutes and 66 km = 66000 m = 6600000 cm

In 60 minutes car travels = 6600000 cm

In 1 minute the car travel = 6600000/60 = 110000 cm

In 1 revolution car travels = 1760/7 cm

The number of revolutions of wheels in 1 minute = The distance traveled by the car in 1 minute/ distance traveled in revolutions

= 110000 ÷ 1760/7

= 110000 × 7/1760

= 437.5 revolutions

In 10 minutes the number of revolutions ,the wheels have = 437.5 ×10 = 4375

Q5.Tick the correct answer in the following and justify your choice. If the perimeter and area of a circle are numerically equal, then the radius of the circle is.

(i) 2 units   (ii) π  units   (iii) 4  units    (iv) 7 units

Ans.

Let the radius of the circle is = r

Circumference of the circle is = 2πr

The area of the circle is = πr²

According to question

πr² = 2πr

r = 2

Hence the radius of the circle is 2 units, so the answer is (i) 2 units

ou can compensate us

Paytm number 9891436286

The money collected by us will be used for the education of poor students who leaves their study because of a lack of money.

NCERT Solutions of Science and Maths for Class 9,10,11 and 12

NCERT Solutions for class 9 maths

Chapter 1- Number SystemChapter 9-Areas of parallelogram and triangles
Chapter 2-PolynomialChapter 10-Circles
Chapter 3- Coordinate GeometryChapter 11-Construction
Chapter 4- Linear equations in two variablesChapter 12-Heron’s Formula
Chapter 5- Introduction to Euclid’s GeometryChapter 13-Surface Areas and Volumes
Chapter 6-Lines and AnglesChapter 14-Statistics
Chapter 7-TrianglesChapter 15-Probability
Chapter 8- Quadrilateral

NCERT Solutions for class 9 science 

Chapter 1-Matter in our surroundingsChapter 9- Force and laws of motion
Chapter 2-Is matter around us pure?Chapter 10- Gravitation
Chapter3- Atoms and MoleculesChapter 11- Work and Energy
Chapter 4-Structure of the AtomChapter 12- Sound
Chapter 5-Fundamental unit of lifeChapter 13-Why do we fall ill ?
Chapter 6- TissuesChapter 14- Natural Resources
Chapter 7- Diversity in living organismChapter 15-Improvement in food resources
Chapter 8- MotionLast years question papers & sample papers

NCERT Solutions for class 10 maths

Chapter 1-Real numberChapter 9-Some application of Trigonometry
Chapter 2-PolynomialChapter 10-Circles
Chapter 3-Linear equationsChapter 11- Construction
Chapter 4- Quadratic equationsChapter 12-Area related to circle
Chapter 5-Arithmetic ProgressionChapter 13-Surface areas and Volume
Chapter 6-TriangleChapter 14-Statistics
Chapter 7- Co-ordinate geometryChapter 15-Probability
Chapter 8-Trigonometry

CBSE Class 10-Question paper of maths 2021 with solutions

CBSE Class 10-Half yearly question paper of maths 2020 with solutions

CBSE Class 10 -Question paper of maths 2020 with solutions

CBSE Class 10-Question paper of maths 2019 with solutions

NCERT Solutions for Class 10 Science

Chapter 1- Chemical reactions and equationsChapter 9- Heredity and Evolution
Chapter 2- Acid, Base and SaltChapter 10- Light reflection and refraction
Chapter 3- Metals and Non-MetalsChapter 11- Human eye and colorful world
Chapter 4- Carbon and its CompoundsChapter 12- Electricity
Chapter 5-Periodic classification of elementsChapter 13-Magnetic effect of electric current
Chapter 6- Life ProcessChapter 14-Sources of Energy
Chapter 7-Control and CoordinationChapter 15-Environment
Chapter 8- How do organisms reproduce?Chapter 16-Management of Natural Resources

NCERT Solutions for class 11 maths

Chapter 1-SetsChapter 9-Sequences and Series
Chapter 2- Relations and functionsChapter 10- Straight Lines
Chapter 3- TrigonometryChapter 11-Conic Sections
Chapter 4-Principle of mathematical inductionChapter 12-Introduction to three Dimensional Geometry
Chapter 5-Complex numbersChapter 13- Limits and Derivatives
Chapter 6- Linear InequalitiesChapter 14-Mathematical Reasoning
Chapter 7- Permutations and CombinationsChapter 15- Statistics
Chapter 8- Binomial Theorem Chapter 16- Probability

CBSE Class 11-Question paper of maths 2015

CBSE Class 11 – Second unit test of maths 2021 with solutions

NCERT solutions for class 12 maths

Chapter 1-Relations and FunctionsChapter 9-Differential Equations
Chapter 2-Inverse Trigonometric FunctionsChapter 10-Vector Algebra
Chapter 3-MatricesChapter 11 – Three Dimensional Geometry
Chapter 4-DeterminantsChapter 12-Linear Programming
Chapter 5- Continuity and DifferentiabilityChapter 13-Probability
Chapter 6- Application of DerivationCBSE Class 12- Question paper of maths 2021 with solutions
Chapter 7- Integrals
Chapter 8-Application of Integrals

Class 12 Solutions of Maths Latest Sample Paper Published by CBSE for 2021-22 Term 2

Class 12 Maths Important Questions-Application of Integrals

Class 12 Maths Important questions on Chapter 7 Integral with Solutions for term 2 CBSE Board 2021-22

Solutions of Class 12 Maths Question Paper of Preboard -2 Exam Term-2 CBSE Board 2021-22

Solutions of class 12  maths question paper 2021 preboard exam CBSE Solution

 

 

 

 

Scroll to Top