Question

A hall is 15 m long and 12 m broad. If the sum of the areas of the floor and the ceiling are equal to the sum of the areas of four walls, the volume of the hall is:
a) 720
b) 900
c) 1200
d) 1800​

Answer 1

Answer:

1200 cubic metres

Step-by-step explanation:

Sum of areas of 4 walls = Sum of areas of floor and ceiling.

Area of wall adjacent to the breadth of the room = Breadth ✕ Height = 12 ✕ h , there are 2 such walls

Area of wall adjacent to the length of the room = length of wall ✕ Height = 15 ✕ h, there are 2 such walls

Area of roof = 15 ✕ 12

Area of floor = 15 ✕ 12

12 ✕ h + 12 ✕ h + 15 ✕ h + 15 ✕ h = 15 ✕ 12 + 15 ✕ 12

2 ✕ 12 ✕ h + 2 ✕ 15 ✕ h = 2 ✕ 15 ✕ 12

2 (12 ✕ h + 15 ✕ h) = 2 (15 ✕ 12)

27h = 15 ✕ 12

Therefore, height h = 20/3 m

Therefore volume = Length ✕ Breadth ✕ Height

= 15 ✕ 12 ✕ (20/3)

= 1200 cubic metres.

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Answer 2

Answer:

900is the right answer

Step-by-step explanation:

b)is right answer