Mental maths trick
Do this sum in your head: Start with 1,000. Add 60. Add 2,000. Add 30. Add 1,000. Add 10.



Answer

5,000? Wrong. Try it again. The correct answer is 4,100. The mind knows that the final 10 will have a 'rounding-up' effect, and expects it to impact the 1,000's instead of the 100's. The mind fails to calculate the final figure properly because it's locked into an expectation.



Pool puzzler
Six friends visited their local club to play at a pool tournament. The competition entry fee was £10 per person. Prize money was £250 for the winner, £100 for the runner-up, and £50 for third-place. There were no other prizes. None of the friends won a single game. There were no disqualifications, and yet the friends came away collectively £150 in profit from having played. How?



Answer

They were the musicians in the band


Whodunnit?
Three of these statements are untrue, so whodunnit?
Mr Red: "Mr Blue did it."
Mr Blue: "Mr Red did it."
Mr Green: "Mr Blue's telling the truth."
Mr Yellow: "Mr Green's not lying."



Answer

Mr Blue done it