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        riddles >> medium >> Machine Problem
        
(Message started by: m_prithvin13 on Aug 29^th, 2005, 3:24am)

Title: Machine Problem
Post by m_prithvin13 on Aug 29^th, 2005, 3:24am

There is a company that has ten machines that makes gold coins. One of the machines is producing coins that are one gram too light. How do you tell which machine out of the ten is producing the coins with the wrong amount of gold weight with only one weighing? :)

Title: Re: Machine Problem
Post by Barukh on Aug 29^th, 2005, 3:50am

What weighing machinery is at our disposal?

Title: Re: Machine Problem
Post by Grimbal on Aug 29^th, 2005, 5:40am

Does a good coin weight 1 gram?

Title: Re: Machine Problem
Post by THUDandBLUNDER on Aug 29^th, 2005, 6:26am

on 08/29/05 at 03:50:31, Barukh wrote:

What weighing machinery is at our disposal?

[hide]Assuming there is the necessary weighing equipment and that we know how much a good coin weighs, we take 1 coin from the 1st machine, 2 from the 2nd machine, 3 from the 3rd machine, etc. On weighing the 55 coins, the magnitude of the discrepancy will tell us which machine is defective.[/hide]

on 08/29/05 at 05:40:43, Grimbal wrote:

Does a good coin weight 1 gram?

Only if a bad coin weighs nothing at all. ::)

Title: Re: Machine Problem
Post by m_prithvin13 on Aug 30^th, 2005, 2:30am

on 08/29/05 at 06:26:27, THUDandBLUNDER wrote:

Assuming there is the necessary weighing equipment and that we know how much a good coin weighs, we take 1 coin from the 1st machine, 2 from the 2nd machine, 3 from the 3rd machine, etc. On weighing the 55 coins, the magnitude of the discrepancy will tell us which machine is defective.

Nice One THUDandBLUNDER

Title: Re: Machine Problem
Post by Grimbal on Aug 31^st, 2005, 9:40am

on 08/29/05 at 06:26:27, THUDandBLUNDER wrote:

Only if a bad coin weighs nothing at all. ::)

And that would make the weighing unnecessary.