The perimeter of floor of rectangular hall is 250m. The cost of the white washing its four walls is Rs. 15000. The height of the room is
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The perimeter of the floor of the rectangular hall is given as 250m. This means:
Perimeter = 2(l + b) = 250m,
where l is the length and b is the breadth of the floor.
From this, we can calculate:
l + b = 250 / 2 = 125m.
The lateral surface area (LSA) of the four walls is given by:
LSA = 2h(l + b),
where h is the height of the room.
Substituting l + b = 125 into the formula, we get:
LSA = 2h(125) = 250h.
The total cost of whitewashing is Rs. 15000, and the cost per square meter is assumed to be Rs. 10 (as it is a standard rate in such problems unless specified otherwise). Thus:
Cost = LSA × Rate,
15000 = 250h × 10.
Simplify to find h:
15000 = 2500h,
h = 15000 / 2500 = 6m.
Thus, the height of the room is 6m, which corresponds to option c) 6m.
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