99^n is such a number begin with 8, least value of n?
(a) 11
(b) 10
(c) 9
(d) n does not exist

• 99(100 - 1) = 9900-99= 9801
  9801(100 - 1) = 980100-9801= 971299
  971299(100 - 1) = 97129900 - 971299 = 96157601
  .....
  .....
  observe the pattern, 98, 97, 96, .... for power of 2, 3, 4, ...
  So for 90 the power could be 10.
  For 11,we get a number starts with 8.
• 8 years agoHelpfull: Yes(27) No(3)
• answer is 11
• 8 years agoHelpfull: Yes(10) No(2)
• answer is d
  n does not exist
  
• 8 years agoHelpfull: Yes(3) No(5)
• answer 11. i tried by using calculator on the computer. good day
• 8 years agoHelpfull: Yes(3) No(2)
• Any odd number whose power is an even number produces an even number as result hence the answer is 10
• 8 years agoHelpfull: Yes(2) No(2)
• 99^11=8.953382543*10^21
  thus the no. begins with 8, which is required.
• 7 years agoHelpfull: Yes(2) No(0)
• answer is 11
• 8 years agoHelpfull: Yes(1) No(0)
• answer is 9
• 8 years agoHelpfull: Yes(0) No(3)
• This is not rigorous, but this is what I will do if I were asked such a question in an exam.
  
  We want (100−1)n=100n−(n1)100n−1+…(100−1)n=100n−(n1)100n−1+….
  
  These are really the terms that contribute to the answer, so definitely n
• 8 years agoHelpfull: Yes(0) No(2)
• answer is 10
• 8 years agoHelpfull: Yes(0) No(1)
• by cross verifying we get n=11
• 8 years agoHelpfull: Yes(0) No(0)
• I calculated it its answe is 11.
• 8 years agoHelpfull: Yes(0) No(0)
• In TCS you can use scntifc calc so it is very easy to solve . it is 11
• 8 years agoHelpfull: Yes(0) No(0)
• 11 will be right ans not confu guy
  
• 7 years agoHelpfull: Yes(0) No(0)