8 Watermelons and two-pan balance puzzle

8 Watermelons and two-pan balance puzzle

Suppose you have 8 watermelons that are exactly the same in appearance.
They are equal in weight except for one, which is heavier than the others.
You want to find the heaviest one by using a two-pan balance.
Each pan can hold any number of watermelons,
and the only items that you can place in the pans are watermelons.

Find the best strategy to determine the heaviest watermelon.
In the worst case scenario,
How many times do you have to use the two-pan balance ?

Click here for Answer

Twice

Explanation :
1st you put 3 watermelons on each side.

If they’re equal you measure the remaining two against one another and you have your answer.

If one side of the scale (in the first weighing of 3 on either side) is heavier then you weigh one of those three on either side.
If they’re equal then the unweighed watermelon is the heaviest
If they’re unequal then you’ll see which is the heaviest.