question_answer

A field is 125 m long and 15 m wide. A tank \[10\text{ }m\times 7.5\text{ }m\times 6\text{ }m\]was dug in it and the earth thus dug out was spread equally on the remaining field. The level of the field thus raised is equal to which one of the following?

A) 15 cm              

B) 20 cm

C) 25 cm

D) 30 cm

Correct Answer: C

Solution :

Area of tank, \[BCDE=10\times 7.5=75\,{{m}^{2}}\]

Area of remaining field s

\[=125\times 15-75=1800\,{{m}^{2}}\]

Volume of earth dug \[=10\times 7.5\times 6=450{{m}^{3}}\]

According to the question, \[1800\times h=450\]

\[\Rightarrow \]   \[h=\frac{1}{4}m=\frac{1}{4}\times 100\,cm=25\,cm\]