My name is PREET.But my son accidentally types the by interchanging a pair of letters in my name.What is the probability that despite this interchange, the name remains unchanged? a.5% b.20% c.25% d.12.5%

• 10%
  son can interchange a pair in 10 combination out of which only one keps the name unchanged.
  10 combinations for change are
  PR
  PE
  PE
  PT
  RE
  RE
  RT
  EE
  ET
  ET
  
  so the probability that despite this interchange, the name remains unchanged = 1/10 = 10%
• 12 years agoHelpfull: Yes(28) No(4)
• 10%
  
  there are 10 possible pairs
  
  out of which 1 will not change my name.
  
  so probability that name remains unchanged = 1/10 = 10%
• 12 years agoHelpfull: Yes(25) No(8)
• the correct answer is 10%.....because we have to select only 2 pairs of letters..and it can be done in 5C2 ways...which is = 10.
  thus, 1/10*100 = 10%.
• 12 years agoHelpfull: Yes(13) No(3)
• 20%.there are 5 possibilities PR,RE,EE,ET,TP.if the pair EE is typed wrong there will be no change in the name.hence 1/5=0.2
  percentage is 0.2*100=20
• 12 years agoHelpfull: Yes(9) No(9)
• 20 % is right answer.
  
• 12 years agoHelpfull: Yes(5) No(8)
• 10%
  Selecting any two - 5C2 = 10[ treating E AND E as distinct)
  Selecting EE = 1
  1/10 * 100 = 10%
• 12 years agoHelpfull: Yes(4) No(1)
• Ans: 25%
  there are only 4 pairs namely, PR, RE, EE, ET
  out of which only 1 pair doesn't cause any effect though we interchange it.
  so, the required probability = 1/4*100 = 25%
• 12 years agoHelpfull: Yes(2) No(9)
• ans is 25%
  since , we need not to change the name..so only EE will change there places..probablity is 1/2*1/2...so 100/4 = 25%
• 12 years agoHelpfull: Yes(2) No(7)
• http://video.google.com/videoplay?docid=-7792915028401524600
• 12 years agoHelpfull: Yes(2) No(0)
• guys.... wats d correct ans now????
  
• 12 years agoHelpfull: Yes(1) No(1)
• need the correct ans.
• 12 years agoHelpfull: Yes(1) No(1)
• can anyone tell me the correct ans
  
• 12 years agoHelpfull: Yes(1) No(1)
• why not 25%
  PR,RP
  RE,ER
  EE,EE
  ET,TE
  because if we write a name we don't consider the first and last letter as a pair
• 12 years agoHelpfull: Yes(1) No(4)
• sry i forgot to include another possibility PR,RE,EE,ET,TP,TR.Hence (1/6)*100=16.66%.pls confirm if my ans s ryt??
• 12 years agoHelpfull: Yes(0) No(7)
• sry this q is not valid mistakely i give the ans for yesteday in place of today
• 12 years agoHelpfull: Yes(0) No(0)
• d:12.5 is correct answer.
  
• 12 years agoHelpfull: Yes(0) No(1)
• wt is the correct answer.............
• 12 years agoHelpfull: Yes(0) No(0)