The radii of the two circular faces of the frustum of a cone are 5 cm and 4 cm. If the height of the frustum is 21 cm, what is it volume in cm3? (π = 22/7)
Show answer & explanation
Correct answer: B
Explanation
Correct Answer is option 2 i.e. 1342
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Concept |
Understanding |
Application |
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Volume of the frustum of cone = 1/3 × π [R2 + r2 + Rr] H |
Radii of the two circular faces of the frustum of a cone are 5 cm and 4 cm. Height of the frustum = 21 cm |
Volume = 1/3 × 22/7 × [52 + 42 + 5 × 4] × 21 ⇒ 22 × [25 + 16 + 20] ⇒ 22 × 61 ⇒ 1342 cm3 |