3 Pills


You are given a prescription which instructs you to take 3 pills, one 
every half hour. How much time will it take you to take all of the 
prescribed medicine?
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ANSWER:
One hour. 

For example:  Let's say it's 10:00 when the doctor gives you the medicine.
You swallow one right away.  At 10:30 (a half hour later) you take the second
one and then the third a half hour later at 11:00. One hour, all 3 pills taken.