CDS Model Paper 5 Mathematics

Volume of mud dug out in two hemispherical pitholes =2×

2

3

πr3=2×

2

3

×

22

7

×23=

2×2×22×8

21

=

704

21

m3
Area on which the mud is spread over
= Area of field − Area of pitholes
=l×b−2×πr2=22×10−2×

22

7

×22
=220−

176

7

=

1540−176

7

=

1364

7

m2
Now, let the rise in level by hm, then
Area of remaining field ×h= Volume of mud dugged out
⇒

1364

7

×h=

704

21

∴ h=

704×7

1364×21

=

16

93

m