Challenging Brain Teaser for August 27 to Sharpen Your Mind

Boiling a Two-Minute Egg with Limited Timers

Challenge Overview

Dr. Johnson aims to boil an egg for exactly two minutes. However, he only has a three-minute hourglass timer and a five-minute hourglass timer at his disposal.

Step-by-Step Solution

To successfully boil the egg for the desired time, Dr. Johnson should follow these steps:

1. Start by boiling the water.
2. Once the water reaches a boil, flip both the three-minute and five-minute timers simultaneously.
3. When the three-minute timer runs out, Dr. Johnson should place the egg in the boiling water.
4. When the five-minute timer runs out, two minutes will have passed since the egg was added. At this point, he should remove the egg from the water.

By following this method, Dr. Johnson can effectively boil the egg for exactly two minutes.