8 identical looking balls

4 shiney stars

You have 8 identical looking balls. 

One is heavier, but you can only use a balance scale twice. 

How do you find the heavier ball?

 




Click here for answer

expand

Step 1: Divide and weigh

Divide the 8 balls into 3 groups: 3 balls, 3 balls, and 2 balls.

Weigh the first 3 balls against the second 3 balls on the balance scale.

If one side is heavier, the heavier ball is in that group of 3.
If the scales balance, the heavier ball is in the remaining 2 balls.

Narrow it down
Scenario 1: Heavier group has 3 balls
Take any 2 balls from this group and weigh them against each other.
If one is heavier → that's the heavy ball.
If they balance → the third ball (not on the scale) is the heavy one.

Scenario 2: Heavier ball is in the 2-ball leftover
Simply weigh the 2 balls against each other. The heavier one shows immediately.

✅ Result: In just 2 weighings, you will always find the heavier ball.




Difficulty
  • Hard
Type
  • Logic
Submit your vote:

Comments

None received

Post your own comment

Name:
Email or web site:
Anti-spam check
To prove you are human, what traffic light color means stop?(Hint: 3 letters, beginning with R)
Comments:
Note: comments may be edited and will not appear until approved