A toy train can make 10 different sounds. Sound changes after every 4mins. Once the train becomes
defective and can make only 2 sounds. Find probability that same sound is repeated 3 times consecutively (1
OUT OF __)?

• Once the train becomes defective and can make only 2 sounds
  let the 2 sounds are o and 1
  probability that same sound is repeated 3 times consecutively is
  P(0)+p(1)= [(1/2)*(1/2)*(1/2)]+[(1/2)*(1/2)*(1/2)]=2/8=1/4
  
• 12 years agoHelpfull: Yes(13) No(1)
• 1/2*1/2*1/2=1/8
• 12 years agoHelpfull: Yes(3) No(2)
• It produces 2 out of 10 due to defective. That 2 sound is repeating for 3 times.
  so, the probability is 1/2^3 and it was mentioned that the same sound is repeating so (1/2^3)*2=1/4
  Note: whenever the word same comes just muitiply by 2 with the probability...
• 12 years agoHelpfull: Yes(3) No(1)
• 1/2*1/2*1/2=1/8
• 12 years agoHelpfull: Yes(1) No(0)
• As the defective toy train now produces 2 sounds then we will take 1/2 and the same sound is repeated 3 times consecutively so we will take 1/3.
  
  now multiply 1/2 * 1/3 = 1/6 - now if 1/6 is in the options then my explanation is correct :)
• 12 years agoHelpfull: Yes(0) No(4)
• @SHIVAM CHOPRA
  i think your analysis might be wrong, as we dont know which sound we should consider, we have to consider consider the probability for both both possible sounds
• 12 years agoHelpfull: Yes(0) No(1)
• @ravi - Might be there are total of 4-5 questions of TCS which I am not able to solve . I am sorry if I am wrong.
• 12 years agoHelpfull: Yes(0) No(0)
• prob :1/2*1/2*1/2=1/8
• 12 years agoHelpfull: Yes(0) No(1)