9 ball riddle

[jolly geoff]

anyone know the answer to this riddle please just cant figure it out ---you have 9 balls same size and colour but one weighs more than the others using balancing scales (as in the scales of justice) you can only weigh them twice to find the odd ball

[kempie]

Split into 3 groups of 3.

Weigh Group 1 against Group 2

If they balance Group 3 contains the heavy ball otherwise the heavy ball is in the heavy group.

Take any 2 balls from the heavy group and weigh 1 against the other.

If they balance then the 3rd (unweighed) ball is the heavy ball otherwise it will be on the balance and obvious.

[jolly geoff]

cheers kempie