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Puzzles

One activity that many of our members enjoy is puzzling! You can test yourself for fun with our brainteasers. Our quizzes and conundrums are updated regularly, so do check back on the page for the latest content, and if you get really good at them, why not find out what your IQ is by booking a Mensa Supervised IQ Test?

5/11/2025 – Bonfire Night

Three lecturers can build a bonfire in 1 hour and 17 minutes

Three students can build a bonfire in 55 minutes

How long will it take all six people working together to build one bonfire?

 

Puzzle courtesy of Mensa member Peter Hooton

  • Show Answer

Answer = 32 minutes 5 seconds

LCM of 77 and 55 is 385.  In 385 minutes, 3 lecturers can build 5 bonfires, and 3 students can build 7 bonfires.

So, a total of 12 bonfires can be built in 385 minutes.

385 ÷12=32 1/12

Puzzles for business use

We are also able to supply puzzle content to businesses, tailored to your needs. This can range from one-off media projects for marketing campaigns and content for newspapers, magazines and company websites, to long-running partnerships and licensing agreements.

Find out more by contacting our marketing team, via: communications@mensa.org.uk