Challenge where you have to make each number from four 4s

  • Topic: Challenge 
  • Thread starter Thread starter Joffe
  • Start date Start date
  • Tags Tags
    Challenge
Join the discussion
Registration is free. Start your own thread to ask a follow-up.
35 replies · 75K views
Physics news on Phys.org
Greg Bernhardt said:
Opening this back up because we still need 89, 91,93!
What are the rules? What is wrong with the 93 above using sqrt and ! .

Is % allowed?
 
I am thinking about the 'rules' and I think 0.4 is a cheat.

It implies 10. The decimalised column is 'Base 10' and infers a number which is only the value '0.4' by virtue of the assumption the base is 10 and thus the decimal column is worth "10^-1".

If you work in the bizarre base of 'Base 1/22.5' (i.e. the number "10" = 2/45ths (denary)) rather than 'Base 10' you can ALSO include a reference to the required base value using a '4'.

[tex].4 + (4/4) (Base { 0.0\bar{4}})[/tex]
and
[tex].4 - (4/4) (Base { 0.0\bar{4}})[/tex]

I am not using zeros any more than '.4' implies base 10, so the solution above should be no more nor less 'allowed' than .4 .

Thoughts?
 
-- "Mathematician #1, what's the Meaning of Life, Power of Love and The Purpose of Man?"
-- "These are non-mathematical thingies! The answer is ∞/∞!"
-- "Mathematician #2, what's Our Place In Universe, The Truth of All and The Reason Of Everything?"
-- "These are non-mathematical thingies! The answer if 0/0!"
-- "Mathematician #3, say you have five 3... what can... "
-- "AHH! Gimme-gimme-gimme! I can make 173 with that! And 81! And 33.3333!
-- "I can make 128! Hey, don't touch my 3!"
-- "Step aside! I can make 0! Hahaha! Take That!"... "No, my 17 is better! You'll get a 3 in your nose!"... "Open way! I can make 3.14159!"... "Ya'll don't think big enough - I can make 357 trillion! Brlrlrlrlr!"... "Hey!"

That's a madhouse :oldbiggrin: !
 
Last edited:
Let ! be the operator such that x! = 89.x/(4+4+4+4)

Therefore

89 = (4+4+4+4)!

When we apply arbitrary rules to what mathematics "means" and when an answer is "right" or "wrong", then it isn't really mathematics any more, it is more like politics or accountancy!