A tale of 8 balls

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You have 8 balls. They are numbered from 1 to 8. The balls are all identical except for the fact that one of them weighs less than the other 7.
You have a balance scale
You are given two chances to use the scale in order to determine which of the 8 balls is lighter than the rest.
How do you do it?

## Hint 1

XYou can weigh any number of balls per try, it does not have to be all 8.

## Hint 2

XStart with an equal number of balls on each side of the scale.

## Hint 3

XStart 3 with balls on each side of the scale.

## Answer:

XYou place balls 1, 2 and 3 on one side of the scale. On the other side, you place balls 4, 5 and 6. If the scale shows them to be of even weight, discard all 6 balls. Weigh balls 7 and 8 and you'll know which is lighter. If balls 1, 2 and 3 and 4, 5 and 6 are not equal weight, take the 3 balls that weigh less. Place 1 of the 3 balls on one side of the scale,and 1 on the other side. If one is not lighter than the other, the remaining ball is the lightest!