how many positive integers are there less than 800 such that all the digits are odd

• 130
  
  Let xyz be a 3 digit number less than 800.The digits should be odd. So y and z can take values 1,3,5,7 and 9.
  x can take values 1,3,5 and 7(since xyz is less than 800)
  
  Total number of 3 digit positive integers that can be formed
  = 4*5*5
  = 100
  Total number of 2 digit positive integers that can be formed (here x=0)
  = 5*5
  = 25
  Total number of 1 digit positive integers that can be formed (here x=0,y=0)
  = 5
  
  Total number of positive integers less than 800 with digits odd
  = 100+25+5
  = 130
  
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