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Question
A field is 200 m long and 150 m broad. There is a plot, 50 m long and 40 m broad, near thefield. The plot is dug 7 m deep and the earth taken out is spread evenly on the field. Byhow many meters is the level of the field raised? Give the answer to the second place of decimal.
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Solution
Volume of earth dug out `=50xx40xx7 m^3`
`=14000m^3`
Let the height of the field rises by h meters
∴volume of filed (cuboidal)=Volume of earth dugout
`⇒200xx150xxh=14000`
`⇒h=(14000)/(200xx150)=0.47m.`
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