Question

find the no.of coins,1.5cm in diameter and 0.2 com thick,to be melted to form a right circular cylinder of height 10 cm and diameter is 4.5 cm.find volumes of both

Answer 1

pi * (4.5 / 2)^2 * 10 = n * pi * (1.5 / 2)^2 * 0.2 
(1/4) * (4.5)^2 * 10 = n * (1/4) * (1.5)^2 * 0.2 
(3 * 1.5)^2 * 10 = n * (1.5)^2 * (1/5) 
5 * 3^2 * (1.5)^2 * 10 = n * (1.5)^2 
5 * 9 * 10 = n 
450 = n 

450