Question

Find the no. Of coins 1.5cm in diameter and 0.2 cm thick to be melted to form a right circular cylinder of height 15cm

Answer 1

Radius of coin=1.5/2=0.75 cm

Volume=pi*0.75*0.75*0.2

=0.1125cm^3*pi

Now the cylinder is 15cm

Volume =pi*r*r*h

=0.75*0.75*15

=8.4375

No of coins=8.4375/0.1125=75

75 coins can be formed