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प्रश्न
A field is in the form of a rectangle of length 18 m and width 15 m. A pit, 7.5 m long, 6 m broad and 0.8 m deep, is dug in a corner of the field and the earth taken out is spread over the remaining area of the field. Find out the extent to which the level of the field has been raised.
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उत्तर
Let the level of the field be risen by h meters volume of the earth taken out from the pit
`7.5xx6xx0.8m^3`
Area of the field on which the earth taken out is to be spread (X)
`=18xx15-7.5xx6=225m^3`
Now, area of the field Xh = volume of the earth taken out from the pit
`⇒225xxh=7.5xx6xx0.8`
`⇒h=36/225=0.1m=16m`
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