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Smoke & mirrors: The answer to the brain-teasing conundrum


We reveal the answer to our brain teaser, which turns out to be a clever smoke and mirrors trick!

The conundrum....
Three men go into a hotel. The receptionist says the room they want to book is £30.

Each man pays £10 and they go to their room.

The receptionist realises she has made a mistake - the room should only have cost £25. So she sends the bellboy to the room with £5 change.

The bellboy can't work out how to split £5 between the three men, so he decides to give each man £1 and keeps £2 for himself.

Each man has therefore now paid £9 for the room = £27.

The bell boy has kept £2. Add that to the £27 = £29

Where is the other £1?

The answer....
This conundrum is really a clever smoke and mirrors trick, because you are being asked to work out a totally illogical sum. If you think about it logically, the three men have paid £27: £25 is in the hotel's till & £2 is in the bellboys pocket. The real sum therefore is -27 + 2 = 25 or + 27 - 2 = 25

But NOT +27+2=29.

It is a coincidence that it makes £29 and makes you think that £1 has gone missing.

If you still don't get it then change the figures. For example, the three men pay £10 each (so still £30) but the receptionist realises the room should have cost £20. The bellboy is given £10 to hand back to the men, but he still only gives each man £1 change and pockets £7. The three men have still paid £27 but you wouldn't add together £27 and £7 and wonder where the extra £4 had come from!

Got a conundrum for a Friday afternoon? Then please email us at


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