A secret can be told only 2 persons in 5
minutes .the same person tells to 2 more persons
and so on . How long will take to tell it to 768
persons ?
a)47.5 min b)50 min c) 500 min d)49 min

• 2^9=512 2^10=1024 for 512 persons time taken=>9*5=45 for telling next 512 persons tym taken =5 min. thus for next 256 persons time taken =(5*256)/512=2.5. total time taken is 45+2.5=47.5
• 11 years agoHelpfull: Yes(14) No(0)
• 2^9=512 for this time will b taken=5*=45min.Then 1024-512=512.it will b minus from 768.i.e 768-512=254.for telling 254 pensons it will take=5*254/512=2.48 min.So total time=45+2.48=47.5(approx)
• 11 years agoHelpfull: Yes(8) No(7)
• 1 person to 2 persons,
  2 to 4 => 2 to 2^2
  4 to 8 => 2^2 to 2^3
  8 to 16 => 2^3 to 2^4
  2^4 to 2^5
  2^5 to 2^6
  2^6 to 2^7
  2^7 to 2^8
  2^8 to 2^9
  512 to 1024 => 2^9 to 2^10
  they asked for 768 members
  i.e., 512/2 = 256
  512+256 = 768
  512 in 5*9 = 45 min
  256 in 5/2 = 2.5 min
  therefore 768 in 47.5 min
• 10 years agoHelpfull: Yes(8) No(2)
• This is just a function that triples itself every 5 minutes. You start with one person, and every generation is x3 so you have 1, 3, 3^2, 3^3, 3^4,
  
  3^n=768
  n=9.16
  
  Answer is 5x9.16=50(approx)min
• 11 years agoHelpfull: Yes(3) No(9)
• the series of saying secrate to people in 5 min is 2 4 8 16 32 64 128 256 512 1024
  which is 2^10 ,and time taken betweem them is 5 min so total time =10*5=50 min
• 11 years agoHelpfull: Yes(3) No(14)
• 2^x = 768
  
  x = log(768) / log(2)
  
  x = 9.5849
  
  Then times that by the doubling time = 5 minutes
  
  9.5849 * 5 = 47.9245 minutes = 47 minutes, 55.47 seconds
• 10 years agoHelpfull: Yes(1) No(0)
• exact ans is 47.92.procedure is same like above
• 10 years agoHelpfull: Yes(0) No(0)