Using the most powerful telescope ever made, scientists observe a class of young aliens on a planet millions of light years away. On the blackboard, their teacher has written these equations: 13 + 15 = 31, 10 x 10 = 100, 6 x 3 = 24 How many fingers do they have? (We count in base ten. What do they count in?)
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Answers :
1) 13/4
2) 729
3) 7

• they have 7 fingers
  
  10 x 10 will always be 100 in any base system so let's take the other two.
  
  Excluding the "10" in the numbers of the first equation, the only way 5 + 3 (8 base 10) is "11" is to take away 1 and the rest is the base, ergo they count 1, 2, 3, 4, 5, 6, 10.
  
  The same with the 6 * 3 is 24.
  
  111111
  111111
  111111
  
  take 1 "1" from the last row to make "10" in each of the other two which makes 24 base 7
• 12 years agoHelpfull: Yes(1) No(1)