Math Is Fun Forum

giacat

Member

Registered: 2010-09-02

Posts: 2

The most difficult problem in south vietnam 2010

topic: has 23 coins, a fake money (not that heavy or lighter than the real coins remaining)

three times with electronic weight balance (which is clearly the deviation between the two sides, if the left-right worse then the current is positive on balance, slightly longer if the right than left on the current balance of is the number of audio, while two sides are equal, the current balance of 0 degrees. find a counterfeit coin.

Bob

Administrator

Registered: 2010-06-20

Posts: 10,626

Re: The most difficult problem in south vietnam 2010

hi giacat,

So hard.  23 ?  If the balance is like the picture below, I can do 12 coins. 

Do we know the weight of a real coin?

Bob

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

soroban

Member

Registered: 2007-03-09

Posts: 452

Re: The most difficult problem in south vietnam 2010

. .

.