Enigmas and puzzles

October 24, 2008

Alex Soupadoupalos had been in the restaurant business a long time. So when his accountant dropped by to discuss his VAT return, Alex had all the figures ready—almost.

"This entry may be a problem," said his accountant. "You've put down £1,000 as your takings for a group of 25 people. HM Revenue may be suspicious of such a round number. Especially since you haven't noted what they each paid."

"I have standard rates," said Alex indignantly. "I charge single women £15, single men £25, and couples £105 for the pair."

"But this was a group. Don't you do a group rate?"

"No—and I don't do threesomes either. This bunch were from the Overpriced Advertising Agency. They didn't care what I charged because they were billing it to the client. So I divided them randomly into single women, single men and couples."

"Why didn't you just make nearly all of them couples?"

"I'm not that greedy," said Alex with an injured look.

How many single women, single men and couples were on the bill?



Prospect invites you to solve the puzzle and send us the solution. Correct answers will be entered into a draw. Five winners will each receive one copy of Ian Stewart's new book Professor Stewart's Cabinet of Mathematical Curiosities (Profile, £10.99).

Send solutions to answer@prospect-magazine.co.uk by 10th October. The winner will be announced in our November issue.