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A class consists of 80 students, 25 of t...

A class consists of 80 students, 25 of them are girls and 55 are boys. If 10 of them are rich and the remaining are poor and also 20 of them are intelligent, then the probability of selecting an intelligent rich girls is a.`5//128` b. `25//128` c. `5//512` d. none of these

A

`5//128`

B

`25//128`

C

`5//512`

D

None of these

Text Solution

Verified by Experts

The correct Answer is:
C
Total number of the students is 80. Total number of boys is 55. Therefore are 10 rich, 70 por, 20 intelligent students in the class. Therefore, required probability is
`underset((I))(1/4)xxunderset((R))(1/8)xxunderset((G))(25/80)=5/512`
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CENGAGE-PROBABILITY II-Exercise (Single)
  1. Five horses are in a race. Mr. A selects two of the horses at random ...

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  2. Let A and B be two events such that p( bar (AuuB))=1/6, p(AnnB)=1/4 a...

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  3. A class consists of 80 students, 25 of them are girls and 55 are boys....

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  4. Events Aa n dC are independent. If the probabilities relating A ,B ,a ...

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  5. Let Aa n dB be two events. Suppose P(A)=0. 4 ,P(B)=p ,a n dP(AuuB)=0. ...

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  6. A box contains 2 black, 4 white, and 3 red balls. One ball is drawn at...

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  7. If any four numbers are slected and they are multiplied, then the prob...

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  8. If odds against solving a question by three students are 2:1, 5:2, and...

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  9. An unbiased coin is tossed 6 times. The probability that third head ap...

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  10. A coin is tossed 7 times. Then the probability that at least 4 consect...

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  11. Three critics review a book. Odds in favour of the book are 5:2, 4:3 ...

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  12. Aa n dB play a game of tennis. The situation of the game is as follows...

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  13. An unbiased cubic die marked with 1,2,2,3,3,3 is rolled 3 times. The ...

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  14. A fair die is tossed repeatedly. A wins if if is 1 or 2 on two consecu...

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  15. Whenever horses a , b , c race together, their respective probabilitie...

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  16. A man alternately tosses a coin and throws a die beginning with the ...

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  17. If p is the probability that a man aged x will die in a year, then the...

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  18. Thirty two players ranked 1 to 32 are playing is a knockout tournament...

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  19. A pair of unbiased dice are rolled together till a sum of either 5 or ...

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  20. A fair coin is tossed 10 times. Then the probability that two heads do...

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