Poisonous Measurements
You are given 8 tablets of the same size, color and odor but one of them is poisonous. The poisonous one is heavier than the normal ones.
You are also given a balance to find the poisonous one.
What is the minimum number of times you have to use the balance to figure out the poisonous tablet?
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First of all, separate the tablets as 3, 3 and 2. Now, put three tablets on one side of the balance and the other three on the other side.
If the balance doesn't show any change: Put the remaining two tablets on either side of the balance and see which goes down.
If the balance shows a change: Take the three tablets which went down. Now put any two tablets on either side of the balance and see if there is any change.
If there isn't any the remaining tablet is the poisonous one. And if there is any the one that goes down is the poisonous!