A Solid metal of cylinder 8cm in diameter and 8cm long is to be made into disc 4cm in diameter and 5cm thick.Assuming no wastage ,how many disc can be made?

Answer 1

First, we need to calculate the volume of the original cylinder and the volume of the disc.

Volume of the original cylinder:
V1 = πr^2h
V1 = π(4cm)^2(8cm)
V1 = 128π cm^3

Volume of the disc:
V2 = π(r^2)h
V2 = π(2cm)^2(5cm)
V2 = 20π cm^3

To find out how many discs can be made, we need to divide the volume of the original cylinder by the volume of one disc:

Number of discs = V1 / V2
Number of discs = 128π / 20π
Number of discs = 6.4

Since we cannot have a fraction of a disc, we can make 6 discs from the original cylinder.