Misc 11 - Chapter 13 Class 12 Probability
Last updated at May 29, 2018 by Teachoo
Transcript
Misc 11 In a game, a man wins a rupee for a six and loses a rupee for any other number when a fair die is thrown. The man decided to throw a die thrice but to quit as and when he gets a six. Find the expected value of the amount he wins / loses. 1st throw : He gets a six P(win) = 1 6 Amount won = 1 2nd throw : He does not get 6 in 1st throw , He gets six in 2nd throw So, P(win) = 5 6 1 6 = 5 36 Amount won = 1 + 1 = 0 3nd throw : He does not get 6 in 1st throw , He does not get 6 in 2nd throw ,He gets six in 3rd throw So, P(win) = 5 6 5 6 1 6 = 25 216 Amount won = 1 1 + 1 = 1 Expected Value = Amount won Probability for all three throws = (1 ) + (0 ) + ( 1 ) = 1 6 + 0 25 216 = 1 6 25 216 = 36 25 216 =
Chapter 13 Class 12 Probability
Serial order wise
About the Author
Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 8 years. He provides courses for Maths and Science at Teachoo. You can check his NCERT Solutions from Class 6 to 12.
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sir why did you not consider the case where he does not get six in any of the three throws?
Hello Davneet,
In this question,
Should we not consider the case that the man does not get a six at all in three throws of the die ?
That is I thought that the sample space of the experiment consists of {(6),(not 6,6),(not 6, not 6, 6), (not 6, not 6, not 6)} where 6 means he gets a six on a die and not 6 means he does not get a 6 ?