how many 3 digit numbers can be formed with 2 consecutive same numbers .
a>160 b> 171 c> 180 D> 256

• answer should be 171 I blv
  
  because
  if you fix the 2nd and 3rd position which can be done in 10 ways and 1st position can take value from 1-9 therefore total ways comes out to b 9*10=90
  plus
  if you fix the 1st nd 2 position which can be done in 9 ways and 3rd position can take 10 values i.e from 0-9, that makes it 9*10=90
  
  total=90+90=180
  now minus the common part like 111,222 to 999
  that is total of 9 numbers..
  therefore finally 180-9=171 which is the answer
• 9 years agoHelpfull: Yes(37) No(8)
• Ans---> 162
  Here is Sol URL---> http://postimg.org/image/3no55swl5/
• 9 years agoHelpfull: Yes(14) No(10)
• 100 to 199= (100,111,112,113,114,115,116,117,118,119,122,133,144,155,166,177,188,199)
  Same 200 to299 and so on
  18*9=162
  And 110,220,330,440,550,660,770,880,990
  So total number=162+9=171
  
• 9 years agoHelpfull: Yes(9) No(1)
• ans is 171 naveen kumar u forget to add these no. 110,220,330,440,550,660,770,880,990
  162 + 9=171
  
• 9 years agoHelpfull: Yes(7) No(1)
• For a 3 digit number if first 2 digits are same then such num if numbers will be 9*9 =81. //(as 0 cant be in front and the number in hundred and thousand place cant be used again).//
  If last 2 digit is same then total such numbers will be 9*10
  
  so total is 81 + 90 = 171
• 9 years agoHelpfull: Yes(6) No(1)
• but there is no option 160 there ..i was also confused... i too got 162 ... @kalyani
• 9 years agoHelpfull: Yes(2) No(1)
• 171.
  100-199 total 19 numbers and same for 200-299, and rest 9 sets.
  so 19*9=171
• 9 years agoHelpfull: Yes(2) No(1)
• Total 3 cases
  Last two digits can be any number from 1 to 9 soo 9 ways then first digit can be any of remaining 8 soo 8x9=72
  last two can be zero then first digit can be in 9 ways i.e 1 to 9 sooo 9 ways
  First digit can't be zero so 1 to 9 now last digit can be remaining or 0 soo 9 ways 9x9=81
  Total 72+9+81=162 ways
  Sooo option A answer
• 9 years agoHelpfull: Yes(0) No(3)
• Is 162 is given in the option....I mark 171
• 9 years agoHelpfull: Yes(0) No(2)
• 161 is write ans
• 7 years agoHelpfull: Yes(0) No(2)