# math

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Metal discs for pet collars have a diameter of 4cm. Each disc is 0.1cm thick. How many discs can be made from 1000cm3 of metal?

• math -

I don't like this question.

There is simple purely mathematical solution
volume of 1 disc = π(2^2)(.1) = .4π cm^3
so number of discs = 1000/(.4π) or 795.8
so they can make 795 discs

Logistically, this is a very ambiguous question
- is the 1000 cm^3 in a block of metal or in sheets?
- are the discs manufactured by pouring liquid metal into a mould ?
- are they stamped ? If so, is the scrap metal used again?
- arhhh! ....

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