Question

One hundred people in your neighborhood always drive to work between 7:30 and 8:00 A.M. and arrive 30 minutes later. Why must two people always arrive at work at the same time, within a minute

Answer 1

Answer: Pigeonhole Principle

Step-by-step explanation:

The Pigeonhole Principle espouses that if there are more objects than the places the objects are supposed to fit into, some of those places will have more than one object. For instance, if there are 20 pigeons and only 19 pigeonholes, one pigeonhole will have more than one pigeon.

If one hundred people in your neighbourhood leave between 7:30 and 8:00 A.M. and arrive 30 minutes later that means they will arrive between 8:00 and 8:30 A.M. This means that 100 people will have to arrive in 30 minutes.

We would have to fit 100 people in 30 minutes. The minutes are the pigeonholes and the people are the pigeons. There will therefore be a situation where at least 2 people will arrive at the same minute because there are many more people than minutes for them to arrive in.