2016 · Q55
A drinking glass of height 24 cm is in the shape of frustum of a cone and diameters of its bottom and top circular ends are 4 cm and 18 cm respectively. If the capacity of the glass is πx cm³, then what is the value of x?
Elementary MathematicsMensuration
- A824
- B1236
- C1628
- D2472
Explanation
Frustum volume = (πh/3)(R²+Rr+r²) with R = 9, r = 2, h = 24. That is (24π/3)(81+18+4) = 8π×103 = 824π. So x = 824 (option A).