Some more Tiffy Brain Teasers

Discussion in 'REME' started by JesterRIP, May 13, 2010.

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  1. A few little mind benders and dilemmas for you:



    1. Using only the number 5, a total of 5 times (using any maths equations) can you arrive at a total of 24?



    2. The year 1978 has an unusual property. When you add the 19 to the 78, the total is the same as the middle two digits (97). What will be the next year to have this same property?



    3. Using only two 2's and any combination of mathematical signs, symbols and functions can you make 5?
     
  2. 1 - ((5x5x5)-5)/5 = 24
     
  3. 3: (2+2+2+2+2)/2=5
     
  4. I think he said only 2 2s, not 6. Unless I've mis-read the question?
     
  5. 2: 2307?
     
  6. Yes - Only two 2's allowed!

    24 (five 5's) - spot on

    2307 - spot on
     
  7. the 2 2s has me stumped.
     
  8. Need a hint?
     
  9. Fugly

    Fugly LE DirtyBAT

    2 (decimal) is 10 in binary. 10/2 = 5.

    :D
     
  10. Haha! You cant change from binary to decimal to suit the equation!!!

    Otherwise you could answer anything like that...
     
  11. yup
     
  12. Think about 1/x and how else 1/x can be written.

    Oh, and there's a decimal point.
     
  13. terroratthepicnic

    terroratthepicnic LE Reviewer Book Reviewer
    1. ARRSE Runners

    The only way I can work it out is.

    the square root of 2 is 1. 1 = .5 of 2.
     
  14. Integer Root ((2 plus 2) factorial)
     
  15. =ROUNDUP(SQRT(FACT(2+2)),0)