Man with Medical Condition and 2 Pills | Interview Puzzles

A man has a medical condition that requires him to take two kinds of pills, call them A and B. The man must take exactly one A pill and exactly one B pill each day, or he will die. The pills are taken by first dissolving them in water.

The man has a jar of A pills and a jar of B pills. One day, as he is about to take his pills, he takes out one A pill from the A jar and puts it in a glass of water. Then he accidentally takes out two B pills from the B jar and puts them in the water. Now, he is in the situation of having a glass of water with three dissolved pills, one A pill and two B pills. Unfortunately, the pills are very expensive, so the thought of throwing out the water with the 3 pills and starting over is out of the question. How should the man proceed in order to get the right quantity of A and B while not wasting any pills?

Solution:
Add one more P1 pill to the glass and let it dissolve.

Take half of the water today and half tomorrow.

So, Percentage of Pill P1 and Pill P2 on both the day in overall be managed equal.

It works under following assumptions:

The dissolved Pills can be used next day.

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