Eight balls, two weighings...

[clarkBENT]

You have eight balls all of the same size. Seven of them weigh the same, and one of them weighs slightly more. How can you find the ball that is heavier by using a balance and only two weighings?

[Newf]

1st weighing: Put 3 balls on each side...If they are equal you have 2 balls left for the second weighing, whichever of those 2 goes down is the heaviest....or

if the first weighing is unequal,

take the 3 balls that went down, put 2 of them on the scales (1 on each side)....if they balance the ball left over out of those 3 is the heaviest...or if they don't balance the ball that goes down is obviously the heaviest...

there you go, 2 weighings and you got your answer