A certain street contains 100 buildings.They are numbered from 1 to 100. How many 9s are used in numbering these buildings?
21
20
19
9

• 20 is the anwerrrrrrrrrrrrrrrrrrrrrr
• 12 years agoHelpfull: Yes(10) No(1)
• here we have b/w 1 to 10 one 9
  and upto 89 we have nine 9's and from 90 to 100 we have 11 9's
  hence the ans is=9+11=20!!
• 12 years agoHelpfull: Yes(3) No(1)
• 9,19,29,39,49,59,69,79,89,90,91,92,93,94,95,96,97,98,99
  so number of 9's=20
• 12 years agoHelpfull: Yes(3) No(2)
• all the numbers from 2 to 9 comes 20times b/w 1-100
• 12 years agoHelpfull: Yes(2) No(0)
• any digit '1-9' between 1-100 appears 20 times.
• 7 years agoHelpfull: Yes(1) No(0)
• all the numbers from 2 to 9 comes 20times b/w 1-100
• 12 years agoHelpfull: Yes(0) No(0)
• use tis formula easily we get answer 2b.where b is base ten.b=10.so answer is twenty.only this formula applicable 1 to 100.
• 12 years agoHelpfull: Yes(0) No(0)
• 1 to 89 ,9 is there =9
  90 to 100 , 9 is =11
  ans=20
• 7 years agoHelpfull: Yes(0) No(0)