Question

a field is 80 m long and 50 M broad in one corner of the fill up it which is 10 M long 7.5 M broad and 8 M deep has been dug out the earth taken out of it is evenly spread over the remaining part of the field find the rise in the level of the field

Answer 1

This question involves volume, and i doubt if volume is covered in 6th standard.
however lets try to find out the quantity of earth taken out= 10 x 7.5 x 8 = 600 cu.m.
Now this has to be uniformly spread on the area= (80 x 50) - (10 x 7.5)= 3925 sq.m
Hence the remaning field will rise by = 600/3925 m = 0.1528m= 15.28 cm

Answer 2

Volume of earth dug out= 10×7.5×8
= 600m³
Area of the remaining field = Area of field- Area dug out.
= 80×50-10×7.5
= 4000-75= 3925m²
We know that,
Volume of earth dug out= Area of the remaining field ×Height(rise in level of field)
600m³= 3925×h
h= 600/3925= 0.15m (approx.)