Okay let's try again, first divide the 12 balls into 3 groups.....let's name them AAAA, BBBB & CCCC: {' y. x* P4 T! {
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First weight....AAAA ^ BBBB, if balance, then problem in C balls, see my post above. If not balance, continue below.www3.tvboxnow.com3 f6 f/ ]' v% d O. @: A" u* O
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From the first weight, let's say AAAA is heavier then BBBB, then either the problem ball is heavier among AAAA, or lighter among BBBB, but all C balls are normal.
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2nd weight....AAAB ^ ACCC, there will be 3 scenarios:
9 L, s& a, L; {% q' r(1) if AAAB is heavier then ACCC, for sure the problem ball is a heavier ball and it's among AAA. Take 2 of these and weight against each other, the heavier ball is the problem, if balance then it's the remaining ball.
9 p8 K- o- u5 T' t2 K(2) if ACCC is heavier then AAAB then weight the A ball in ACCC against a normal C ball, if balance then the problem ball is the B ball in AAAB and it's a lighter ball. If heavier then this is the problem ball. (note it cannot be lighter)
/ X0 J" F& ^" _3 w6 `, \$ V(3) if balance then the problem ball is one of the 3 B balls not touched in the 2nd weight and it's a lighter ball. Take 2 of these B balls and weight against each other. If balance then the other B ball is the problem. If not balance then the lighter ball is the problem. |