easylogic

A doctor gives you three pills and tells you to take one every half an hour. How long will the pills last?

One hour. If you take the first pill at 1:00, the second at 1:30, and the third at 2:00, the pills have run out and only an hour has passed.

Why this works

This riddle plays on the timing and sequence of taking the pills. While it might seem like the pills would last longer because you take them every half hour, the key is in the total duration: after taking the first pill at 1:00, you take the second at 1:30, and the last one at 2:00. By the time you take the third pill, only one hour has passed, meaning the pills last a total of one hour, not three! It's a clever twist that makes you think about the intervals versus the overall time.

Common Wrong Answers

“Two hours”

This answer incorrectly assumes that the pills last for the duration between taking them rather than counting the time when the last pill is taken.

“Thirty minutes”

This answer suggests that the pills will only last for the time it takes to take the first pill, ignoring the timing of the subsequent pills.

“One and a half hours”

This answer mistakenly adds the time intervals together, failing to recognize that the last pill is taken at the one-hour mark.

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