Question

Ramesh had a field of length 20 m and width 14 m. During lockdown, he had ample amount of free time, so he decided to do some tree plantation on the field. For doing so first of all he want to make a deep pit, he will put all the fruit and vegetable waste and biodegradable waste to make it compost, used in farming. For this he dug a deep well of diameter 7 m in the corner of the field. The earth taken out from the pit is spread uniformly on the remaining field.

Find:

(i) How much earth is taken out from deep pit?

(ii) Upto what height the field is raised when earth taken out from pit is spread on the field? 

 Use (pi = 22/7)

Answer 1

l = 20 m

b = 14

2r = 7m

h = 7 m

(i) \(\therefore \) Earth taken out from the well = Volume of well

\(= \pi r^2 h \)

\(= \frac{22}7 \times \frac 72 \times \frac 72 \times 7\)

\(= \frac {539}2 m^2\)

\(= 269.5 m^2\)

(ii) Raised height = \(\frac{\text{Volume of well}}{\text{Area of field}}\)

\(= \frac{539}{2} \times \frac 1{20 \times 14}\)

\(= \frac{77}{80} m\)

\(= 0. 9625 m\)