If the diameter of the base of a cone is 24 cm and its curved surface area is 1395 cm², then its volume (in cm³) is: Take π = 22/ 7
Show answer & explanation
Correct answer: C
Explanation
The correct answer is Option 3 i.e. 5280.
Curved surface area = 139537 cm2
πrl = (9768/7)
⇒ (22/7) × 12 × l = 9768/7 ⇒ l = (9768 × 7)/(12 × 7 × 22)
⇒ l = 9768/(12 × 22) = 37
h = √l2 - r2 ⇒ h = √(37)2 - (12)2 ⇒ h = √1369 - 144 ⇒ h = √1225 ⇒ h = 35 cm
Volume of cone = (1/3) × π × r2 × h ⇒ (1/3) × (22/7) × (12)2 × 35 = 5280 cm3