Toppers Study Toppers Study Toppers StudyDetailed NCERT Solutions for 9 Mathematics 13. Surface Areas and Volumes to simplify learning. Understand chapters clearly and practice with free solutions for better results.
Detailed NCERT Solutions for 9 Mathematics 13. Surface Areas and Volumes to simplify learning. Understand chapters clearly and practice with free solutions for better results.
Preparing for exams becomes easier with Exercise 13.3. Whether you are studying for board exams or mid-term exams, 9 Mathematics Chapter 13. Surface Areas and Volumes solutions provide quick revising points, well-structured answers, and additional practice material to help you score better.
ncert_solutionsEXERCISE 13.3
Assume that π = 
, unless stated otherwise.
1. Diameter of the base of a cone is 10.5 cm and its slant height is 10 cm. Find its curved surface area.
Solution:
Diameter = 10.5 cm Þ radius = 5.25, height = 10 cm
Curved surface area of cone = πrl
Þ × 5.25 × 10
Þ × 52.5
Þ 165 cm2
2. Find the total surface area of a cone, if its slant height is 21 m and diameter of its base is 24 m.
Solution:
Slant height = 21 m , diameter = 24 m Þ radius = 12 m
Total surface area of cone = πr(l + r)
3. Curved surface area of a cone is 308 cm2 and its slant height is 14 cm. Find
(i) radius of the base and (ii) total surface area of the cone.
Solution:
CSA of cone = 308 cm2, height = 14 cm
(i) CSA of cone = 308 cm2
4. A conical tent is 10 m high and the radius of its base is 24 m. Find
(i) slant height of the tent.
(ii) cost of the canvas required to make the tent, if the cost of 1 m2 canvas is 70.
Solution:
Height = 10 cm, radius = 24 m
l2 = h2 + r2
l2 = 102 + 242
l =
l = 26 m
(ii) curved surface area of cone = πrl
5. What length of tarpaulin 3 m wide will be required to make conical tent of height 8 m and base radius 6 m? Assume that the extra length of material that will be required for stitching margins and wastage in cutting is approximately 20 cm (Use π = 3.14).
Solution:
Wide = 3 m , height = 8 , radius = 6 m
l2 = r2 + h2
l2 = 62 + 82
l =
l = 10 m
Curved surface area of cone = πrl
Þ 3.14 × 6 × 10
Þ 31.4 × 6
Þ 188.4 m2
6. The slant height and base diameter of a conical tomb are 25 m and 14 m respectively. Find the cost of white-washing its curved surface at the rate of 210 per 100 m2.
Solution:
Length = 25 m, diameter = 14 m, radius = 7 m
Curved surface area of cone = πrl
7. A joker’s cap is in the form of a right circular cone of base radius 7 cm and height 24 cm. Find the area of the sheet required to make 10 such caps.
Solution:
Radius = 7 cm, height = 24 cm
l2 = r2 + h2
l2 = 72 + 242
8. A bus stop is barricaded from the remaining part of the road, by using 50 hollow cones made of recycled cardboard. Each cone has a base diameter of 40 cm and height 1 m. If the outer side of each of the cones is to be painted and the cost of painting is 12 per m2, what will be the cost of painting all these cones? (Use π = 3.14 )
Solution:
Diameter = 40 cm, radius = 20 cm, height = 1 m
l2 = r2 + h2
l2 = 0.22 + 12
Exercise 13.3 are created by experts to give step-by-step explanations. Around 60–70% of exam questions are based on NCERT concepts. Our 9 Mathematics Chapter 13. Surface Areas and Volumes solutions help you understand the core concepts and practice effectively.
Revision is the key to exam success. Our notes for 9 Mathematics highlight important formulas, key definitions, and exam-ready points from Chapter 13. Surface Areas and Volumes. These quick revision notes make last-minute preparation easy.
Every NCERT chapter ends with exercises, and solving them is crucial. Our Exercise 13.3 include complete solutions for 9 Mathematics Chapter 13. Surface Areas and Volumes exercises. With step-by-step answers, you gain clarity and confidence to attempt similar exam questions.
To boost your preparation, we also provide additional important questions with answers. These are prepared from previous year board papers, sample papers, and important concepts of Chapter 13. Surface Areas and Volumes. Practicing these ensures you are well-prepared for both board and mid-term exams.
Our Exercise 13.3 are useful for both board exams and mid-term exams. For 9 Mathematics, we provide notes, exercises, and important Q&A so that you can revise smartly and write perfect answers in exams.
In short, Exercise 13.3 for 9 Mathematics Chapter 13. Surface Areas and Volumes are a complete study package. With quick revising points, NCERT exercises, and additional important questions, you can prepare effectively for exams. Make these solutions your study companion and excel in your academic journey.
Go to other Class
Download worksheets and assignments for better practice and revision.