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प्रश्न
The length of a hall is 18 m and the width 12 m. The sum of the areas of the floor and the
flat roof is equal to the sum of the areas of the four walls. Find the height of the hall.
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उत्तर
Length of the hall = 18m
Width of hall = 12m
Now given,
Area of the floor and the flat roof = sum of the areas of four walls.
`⇒2lb=2lh+2bh`
`⇒lb= lh+bh`
`⇒h=(lb)/(l+b)=(18xx12)/(18+12)=(216)/30`
`=7.2m`
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