A patient in a hospital is given soup daily in a cylindrical bowl of diameter 7 cm.
Question. A patient in a hospital is given soup daily in a cylindrical bowl of diameter 7 cm. If the bowl is filled with soup to a height of 4 cm, how much soup the hospital has to prepare daily to serve 250 patients?

$\left[\right.$ Assume $\left.\pi=\frac{22}{7}\right]$

Solution:

Radius $(r)$ of cylindrical bowl $=\left(\frac{7}{2}\right) \mathrm{cm}=3.5 \mathrm{~cm}$

Height (h) of bowl, up to which bowl is filled with soup = 4 cm

Volume of soup in 1 bowl $=\pi r^{2} h$

$=\left(\frac{22}{7} \times(3.5)^{2} \times 4\right) \mathrm{cm}^{3}$

$=(11 \times 3.5 \times 4) \mathrm{cm}^{3}$

$=154 \mathrm{~cm}^{3}$

Volume of soup given to 250 patients $=(250 \times 154) \mathrm{cm}^{3}$

$=38500 \mathrm{~cm}^{3}$

$=38.5$ litres
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