Q10 of 24 Page 227

In a right circular conical tent 11 persons can stay. For each person 4m2 space in the base and 20m3 air are necessary. Let us determine the height of the tent put up exactly for 11 persons.

Let, base radius of the tent = r m


Height of the tent = h m


Space in the base in the tent = πr2 m2


According to problem,


⇒ πr2 = 11 × 4


⇒ πr2 = 44 ……….. (1)


Volume of air in the tent = ⇒ πr2h/3


According to problem,


⇒ πr2h/3 = 11 × 20


⇒ 44 × h = 660 [putting the value from (1)]


⇒ h = 15


∴ height of the tent = 15 m


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