A hemispherical bowl of radius 9 cm contains a liquid. This liquid is to be filled into cylindrical small bottles of diameter 3 cm and height 4 cm.
Question:

A hemispherical bowl of radius 9 cm contains a liquid. This liquid is to be filled into cylindrical small bottles of diameter 3 cm and height 4 cm. How many bottles will be needed to empty thee bowl?
(a) 27
(b) 35
(c) 54
(d) 63

Solution:

(c) 54

Number of bottles $=\frac{\text { volume of bowl }}{\text { volume of } 1 \text { bottle }}$

$=\frac{\frac{2}{3} \times \pi \times 9^{3}}{\pi \times 1.5^{2} \times 4}$

$=\frac{2 \times 729}{2.25 \times 12}=54$