13. Surface Areas and Volumes Class 9 Mathematics Solutions English Medium-Exercise 13.4
13. Surface Areas and Volumes Class 9 Mathematics Solutions English Medium-Exercise 13.4 Get chapter-wise detailed explanations, step-by-step answers, important questions and exam-ready study material in Hindi and English medium.
Topics Covered In This Article
13. Surface Areas and Volumes Class 9 Mathematics Solutions English Medium-Exercise 13.4, NCERT Solutions for CBSE Board Classes 6 to 12, ncert solutions for all classes, NCERT SOLUTIONS, online NCERT solutions, NCERT, ncert, ncert solutions, ncert solutions for board exams, ncert Maths solution, Mathematics, ncert science solutions, ncert English book solutions, ncert Hindi book solutions, ncert Social Science book solutions, ncert accounts book solutions, Computer Education, solved question answer for all exercise
13. Surface Areas and Volumes Class 9 Mathematics Solutions English Medium-Exercise 13.4
NCERT Solutions for Class 9 are specially prepared according to the latest CBSE syllabus (2026-27) to help students understand every concept clearly. These solutions provide step-by-step explanations, accurate answers, and exam-oriented guidance for all chapters. Class 9 students can improve their problem-solving skills, strengthen conceptual understanding, and prepare confidently for school as well as board examinations. All questions are solved in a simple and easy-to-understand language for both Hindi and English medium learners.
13. Surface Areas and Volumes Class 9 Mathematics Solutions English Medium-Exercise 13.4
NCERT Solutions Class 9 Mathematics English Medium
13. Surface Areas and Volumes
Topic: Exercise 13.4
Exercise 13.4
Assume π = 22/7 , unless stated otherwise.
Q1. Find the surface area of a sphere of radius:
(i) 10.5 cm (ii) 5.6 cm (iii) 14 cm
Solution:

Q2. Find the surface area of a sphere of diameter:
(i) 14 cm (ii) 21 cm (iii) 3.5 m
Solution:
(i) Surface area of sphere = 4πr2

Q3. Find the total surface area of a hemisphere of radius 10 cm. (Use π = 3.14)
Solution:
Total surface area of hemisphere = 3πr2
⇒ 3 × 3.14 × 10 × 10
⇒ 3 × 314
⇒ 942 cm2
Q4. The radius of a spherical balloon increases from 7 cm to 14 cm as air is being pumped into it. Find the ratio of surface areas of the balloon in the two cases.
Solution:
Surface area of sphere = 4πr2

Q5. A hemispherical bowl made of brass has inner diameter 10.5 cm. Find the cost of tin-plating it on the inside at the rate of 16 per 100 cm2.
Solution:
Curved surface area of hemisphere = 2πr2
Q6. Find the radius of a sphere whose surface area is 154 cm2.
Solution:
Area = 154 cm2
Surface area of sphere = 4πr2

Q7. The diameter of the moon is approximately one fourth of the diameter of the earth. Find the ratio of their surface areas.
Solution:
Let the diameter of earth = x

Q8. A hemispherical bowl is made of steel, 0.25 cm thick. The inner radius of the bowl is 5 cm. Find the outer curved surface area of the bowl.
Solution:
Inner radius = 5 cm, width = 0.25 cm, radius = 5.25 cm
Curved surface area of hemisphere = 2πr2

⇒ 44 × 0.75 × 5.25
⇒ 173.25
Q9. A right circular cylinder just encloses a sphere of

radius r (see Fig. 13.22). Find
(i) surface area of the sphere,
(ii) curved surface area of the cylinder,
(iii) ratio of the areas obtained in (i) and (ii).
Solution:
Radius of sphere = r, radius of cylinder = r + r = 2r
(i) surface area of sphere = 4πr2
(ii) curved surface area of cylinder = 2πrh
⇒ 2πr(2r)
⇒ 4πr2
All Topics From 13. Surface Areas and Volumes
See other sub-topics of this chapter:
1. Exercise 13.1 2. Exercise 13.2 3. Exercise 13.3 4. Exercise 13.4 5. Exercise 13.5 6. Exercise 13.6 7. Exercise 13.7 8. Exercise 13.8 9. Exercise 13.9NCERT Solutions Class 9 Hindi and English Medium – Complete Study Material
NCERT Solutions Class 9 students ke liye specially CBSE latest syllabus (2026-27) ke according prepare kiye gaye hain. Yeh solutions Hindi aur English medium dono ke liye available hain, jisse har student apni language preference ke hisaab se padh sakta hai. Har chapter ke sabhi prashnon ke step-by-step answers diye gaye hain jo concept clarity aur exam preparation me madad karte hain.
Chapter-Wise Detailed Explanations
Class 9 ke liye diye gaye Chapter Wise NCERT Solutions me har question ka detailed aur easy explanation diya gaya hai. Chahe aap CBSE Board Exam Preparation kar rahe ho ya school test ke liye revise kar rahe ho, yeh solutions aapko complete understanding denge. Har answer simple language me likha gaya hai jisse students concepts ko easily grasp kar saken.
Hindi and English Medium Support
Students Hindi aur English medium dono me NCERT Book Solutions Class 9 access kar sakte hain. Yeh dual language support un students ke liye helpful hai jo apni regional language me better samajhna chahte hain. Sabhi answers CBSE Latest Syllabus 2026-27 ke anusaar update kiye gaye hain.
Important Features of NCERT Solutions
- Class 9 NCERT Solutions PDF
- CBSE Class 9 Study Material
- NCERT Book Questions and Answers
- Exam Oriented Important Questions
- Step-by-Step Detailed Solutions
- Concept Clarity and Revision Notes
Why Students Should Use NCERT Solutions?
Aaj ke competitive environment me sirf textbook padhna kaafi nahi hota. NCERT Solutions for Class 9 students ko practice aur conceptual understanding dono provide karte hain. Yeh solutions unhe exam pattern samajhne, frequently asked questions practice karne aur high score achieve karne me madad karte hain. Regular practice se students apne weak topics ko improve kar sakte hain.
Best Resource for Exam Preparation
Agar aap Class 9 CBSE Preparation ke liye ek trusted aur reliable source dhundh rahe hain, to yeh NCERT Solutions perfect choice hain. Yeh study material school exams, unit tests, half-yearly aur annual exams ke liye equally useful hai. Har chapter ke answers accurate, verified aur student-friendly format me diye gaye hain.
Isliye agar aap NCERT Solutions Class 9 Hindi and English Medium search kar rahe hain, to yahan aapko complete chapter-wise solutions milenge jo aapki academic journey ko strong aur confident banayenge.
Welcome to ATP Education
ATP Education