All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars
 perplexus dot info

 One of Sixteen (Posted on 2015-12-29)
I have two sets of 8 coins. In one set the coins weigh 30g each, in the other set the coins weigh 31g each.
Unfortunately they got mixed together in one big pile of 16 coins. I want to identify one coin. It can be from either set.

(Easy) Using a balance scale, identify a coin in four weighings.

(Hard) Identify a coin in just three weighings.

 See The Solution Submitted by Brian Smith Rating: 4.0000 (3 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
 re: What's the problem? (and a spoiler) | Comment 7 of 12 |
(In reply to What's the problem? (and a spoiler) by Steve Herman)

The problem is to identify any one coin.  It does not need to be a specific coin.  Broll's solution is correct.

I don't think it is possible to choose and identify a specific coin in just three weighings.

 Posted by Brian Smith on 2015-12-31 13:06:07

 Search: Search body:
Forums (0)