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Question
A rectangular field is 70 m long and 60 m broad. A well of dimensions 14 m × 8 m × 6 m is dug outside the field and the earth dug-out from this well is spread evenly on the field. How much will the earth level rise?
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Solution
\[\text { Dimension of the well = 14 m } \times 8 m \times 6 m \]
\[\text { The volume of the dug - out earth = 14 }\times 8 \times 6 = 672 m^3 \]
\[\text { Now, we will spread this dug - out earth on a field whose length, breadth and height are 70 m, 60 m and h m, respectively } . \]
\[\text { Volume of the dug - out earth = length } \times \text { breadth }\times \text { height }= 70 \times 60 \times h\]
\[ \Rightarrow 672 = 4200 \times h\]
\[ \Rightarrow h = \frac{672}{4200} = 0 . 16 m\]
\[\text { We know that 1 m = 100 cm }\]
\[ \therefore \text { The earth level will rise by 0 . 16 m = 0 . 16 } \times 100 cm = 16 cm .\]
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