QUIZ: Another coin puzzle

[Lotana]

There are 10 large bags full of coins. All coins in 9 of the bags are good. The remaining bag is full of fake coins. A good coin weighs 10 gram; a fake coin weighs 9.5 gram. How to identify the fake coins bag with just one weighing allowed using post office scales (well suppose they are precise to a tenth of a gram)?



Say cheese :p

Lotana

[Steve Navra]

What??

Will no-one even try Lotana's coin gem??????

Personally I need a day or two to recover from the oddball one, I still have unbalnced scales swimming around in my head!

Steve

[Simon]

I have done this one before so I wont answer it.

Whilst it seems really hard I think it is much simpler than the ball one and just needs some creative thinking.

Good luck,

[Steve Navra]

Originally posted by Simon

I think it is much simpler than the ball one

My OATH!

Steve :)

[EJS]

Take 1 coin from each bag, numbering them with their corresponding bag

Add them to the scales 1 at a time to each side. When the scales tip, you have the fake.

Eddie

[Steve Navra]

Hey EJS,

Surely the scales tip each time you add a coin to the opposite side?? :D :D :D

Steve

[Steve Navra]

One coin from the first bag + 2 coins from the second bag + 3 coins from the third bag . . . 10 coins from the tenth bag and weigh them simultaneously.

Now the total should be 550 grams. (That is if all the coins correctly weighed the 10 grams)

Now because the counterfeit weigh 0.5 grams less there will be a proportionate lesser weight to the number of counterfeit coins.

So if for example bag 2 were the counterfeits, then you would have 2 X 0.5 grams less than the 550 grams. (549 grams)

Therefore bag two would be the counterfeits!


I feel so gooooood!

Steve
:D

[Luke]

!

[Lotana]

Ok Steve you deserved the whole cheesecake!

:p

Lotana