Find out about yourselfJoin Mensa nowBrowse our shop

Mensa Group

Were you previously a member? Rejoin

Are you a member of another National Mensa? Become a Guest member

Mensa Brainteasers

Week 35 - Thursday 

A 110 yard long train, travelling at 80 mph, enters a tunnel of half a mile in length.

How many seconds will elapse between the moment the front of the train enters the tunnel and the moment the end of the train clears the tunnel?



04 Sep 2017
Reveal answer