how many 4 digit number are there that do not have 3 and 6 digit

• ans:3584
  consider 4 blanks _ _ _ _
  1st blank can be filled in 7c1 ways (0,3,6 are neglecetd)
  2st blank can be filled in 8c1 ways (0 considered along with 1,2,4,5,7,8,9)
  3st blank can be filled in 8c1 ways
  4st blank can be filled in 8c1 ways
  therefore total 4 digit num without 3 and 6 is 7*8*8*8=3584
• 11 years agoHelpfull: Yes(45) No(0)
• 7*8*8*8=3584
• 11 years agoHelpfull: Yes(4) No(0)
• 3584
  7*8*8**=3584
  
• 11 years agoHelpfull: Yes(3) No(0)
• 1000->9999:with out any 3 and 6 is:3584
• 11 years agoHelpfull: Yes(2) No(0)
• how can u consider repitetion is allowed
  
• 11 years agoHelpfull: Yes(1) No(1)
• 9*8*8*8=4608
• 11 years agoHelpfull: Yes(0) No(4)