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Volume of combined solids: Class 10 practice

The volume of a solid made of simple shapes is the sum of their volumes. Read the method, follow the three worked examples, then try the six questions.

What you should know first

  • Volumes of cone, cylinder, sphere

The idea behind volume of combined solids

The volume of a solid made of simple shapes is the sum of their volumes. Find each part's dimensions carefully — total height minus the hemisphere's radius gives the cone or cylinder height.

Step-by-step method

  1. Split the solid into cones, cylinders, hemispheres.
  2. Work out each part's dimensions.
  3. Add (or subtract) the volumes.
  4. Use the π the question asks for.

Worked example 1 (Basic)

A solid is a cylinder of radius 14 cm and height 6 cm with a hemisphere of the same radius on top. Find its volume (π = 22/7).

  1. Cylinder = 3696.00 cm³
  2. Hemisphere = 5749.33 cm³
  3. Total = 9445.33 cm³
  4. Answer: 9445.33 cm³

Worked example 2 (Standard)

A toy is a cone of radius 3.5 cm on a hemisphere of the same radius; total height 15.5 cm. Find its volume (π = 22/7).

  1. Cone height = 15.5 − 3.5 = 12 cm
  2. Cone = 154.00, hemisphere = 89.83
  3. Total = 243.83 cm³
  4. Answer: 243.83 cm³

Worked example 3 (Challenge)

A cone of radius 7 cm and height 4 cm is hollowed out of a cylinder of the same radius and height. Find the remaining volume (π = 22/7).

  1. Cylinder − cone = 616.00 − 205.33
  2. = 410.67 cm³
  3. Answer: 410.67 cm³

Common mistakes and misconceptions

  • Using total height for the cone
  • Adding surface areas of hidden faces

Practice questions

  1. (Basic) A solid is a cylinder of radius 7 cm and height 8 cm with a hemisphere of the same radius on top. Find its volume (π = 22/7).
  2. (Basic) A solid is a cylinder of radius 7 cm and height 10 cm with a hemisphere of the same radius on top. Find its volume (π = 22/7).
  3. (Standard) A toy is a cone of radius 7 cm on a hemisphere of the same radius; total height 15 cm. Find its volume (π = 22/7).
  4. (Standard) A toy is a cone of radius 7 cm on a hemisphere of the same radius; total height 19 cm. Find its volume (π = 22/7).
  5. (Challenge) A cone of radius 7 cm and height 12 cm is hollowed out of a cylinder of the same radius and height. Find the remaining volume (π = 22/7).
  6. (Challenge) A cone of radius 7 cm and height 8 cm is hollowed out of a cylinder of the same radius and height. Find the remaining volume (π = 22/7).

Answer key with full working

  • Q1: Cylinder = 1232.00 cm³ → Hemisphere = 718.67 cm³ → Total = 1950.67 cm³ → Answer: 1950.67 cm³
  • Q2: Cylinder = 1540.00 cm³ → Hemisphere = 718.67 cm³ → Total = 2258.67 cm³ → Answer: 2258.67 cm³
  • Q3: Cone height = 15 − 7 = 8 cm → Cone = 410.67, hemisphere = 718.67 → Total = 1129.33 cm³ → Answer: 1129.33 cm³
  • Q4: Cone height = 19 − 7 = 12 cm → Cone = 616.00, hemisphere = 718.67 → Total = 1334.67 cm³ → Answer: 1334.67 cm³
  • Q5: Cylinder − cone = 1848.00 − 616.00 → = 1232.00 cm³ → Answer: 1232.00 cm³
  • Q6: Cylinder − cone = 1232.00 − 410.67 → = 821.33 cm³ → Answer: 821.33 cm³

Syllabus note

This skill is listed under "Surface Areas and Volumes" for Class 10 in the NCERT/CBSE books. ICSE, IGCSE, IB and state boards may teach it in a different chapter or year.

Answers on this page are generated and automatically re-checked by a second, independent calculation. They have not been reviewed by a teacher — if you spot a problem, tell us on WhatsApp.

Related practice and notes

Frequently asked questions

Which chapter is volume of combined solids in?

"Surface Areas and Volumes", Class 10 Maths (NCERT/CBSE). Other boards may place it differently.

How were the answers checked?

Answers on this page are generated and automatically re-checked by a second, independent calculation. They have not been reviewed by a teacher — if you spot a problem, tell us on WhatsApp.

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