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Fun with Ruby - to_s 

irb> 1
=> 1

irb> 1.to_s
=> "1"

irb> 1.to_s * 2
=> "11"

irb> "1" *2
=> "11"

irb> 1.to_s *2
=> "1" # huh?

#let's try that again with 2....

irb> 2.to_s
=> "2"

irb> 2.to_s * 2
=> "22" # good

irb> "2" *2
=> "22"

irb> 2.to_s *2
=> "10" # wtf?
Sometimes a space makes all the difference. Ruby's 
#to_s
on an Integer takes an optional parameter which specifies the base you are working in. In this case, passing in *2 has set our base to binary.
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