Home
Class 12
MATHS
The probabilities of a student getting I...

The probabilities of a student getting I, II and III division in an examination are `(1)/(10),(3)/(5)` and `(1)/(4)\ ` respectively. The probability that the student fails in the examination is

A

a) `(197)/(200)`

B

b) `(27)/(100)`

C

c) `(83)/(100)`

D

d) none of these

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we first need to understand the probabilities given for the divisions and then find the probability of failing the examination. ### Step-by-Step Solution: 1. **Identify the Given Probabilities:** - Probability of getting I division (P(I)) = \( \frac{1}{10} \) - Probability of getting II division (P(II)) = \( \frac{3}{5} \) - Probability of getting III division (P(III)) = \( \frac{1}{4} \) 2. **Calculate the Total Probability of Getting a Division:** To find the probability of failing, we first need to calculate the total probability of getting any division (I, II, or III). This is done by adding the probabilities of getting each division: \[ P(I) + P(II) + P(III) = \frac{1}{10} + \frac{3}{5} + \frac{1}{4} \] To add these fractions, we need a common denominator. The least common multiple (LCM) of 10, 5, and 4 is 20. - Convert each probability to have a denominator of 20: \[ P(I) = \frac{1}{10} = \frac{2}{20} \] \[ P(II) = \frac{3}{5} = \frac{12}{20} \] \[ P(III) = \frac{1}{4} = \frac{5}{20} \] - Now add them: \[ P(I) + P(II) + P(III) = \frac{2}{20} + \frac{12}{20} + \frac{5}{20} = \frac{19}{20} \] 3. **Calculate the Probability of Failing:** The probability of failing (P(Fail)) is the complement of the probability of getting any division: \[ P(Fail) = 1 - (P(I) + P(II) + P(III)) \] \[ P(Fail) = 1 - \frac{19}{20} = \frac{1}{20} \] ### Final Answer: The probability that the student fails in the examination is \( \frac{1}{20} \). ---

To solve the problem, we first need to understand the probabilities given for the divisions and then find the probability of failing the examination. ### Step-by-Step Solution: 1. **Identify the Given Probabilities:** - Probability of getting I division (P(I)) = \( \frac{1}{10} \) - Probability of getting II division (P(II)) = \( \frac{3}{5} \) - Probability of getting III division (P(III)) = \( \frac{1}{4} \) ...
Promotional Banner

Topper's Solved these Questions

  • MEAN VALUE THEOREMS

    RD SHARMA|Exercise Solved Examples And Exercises|110 Videos
  • RELATIONS

    RD SHARMA|Exercise Solved Examples And Exercises|197 Videos

Similar Questions

Explore conceptually related problems

The probabilities of a student getting first class or second class or third class in an examination are (2)/(7) , (3)/(5) ,(1)/(10) respectively . The probability that the students fails is .

The sum of probabilities of two students getting distinction in their final examinations is 1.2.

Many of the students _____ failed in the examination. (has/have)

A student appears for tests I, II and III. The student is successful if the passes either in tests I and II or tests I and III. The probabilities of the student passing in tests I, II and III are p,q and (1)/(2) , respectively. If the probability that the student is successful, is (1)/(2) , then

A student appears for test I and II.The student is successful if he passes either in test I or test II.The probability of the student passing in test I and II are p and (1)/(3) respectively.If the probability that the student is successful is (1)/(2) then find the value of p.

RD SHARMA-PROBABILITY-Solved Examples And Exercises
  1. Four cards are drawn at a time from a pack of 52 playing cards. Find t...

    Text Solution

    |

  2. A and B are two events such that P(A)=0. 25 and P(B)=0. 50. The prob...

    Text Solution

    |

  3. The probabilities of a student getting I, II and III division in an ...

    Text Solution

    |

  4. India plays two matches each with West Indies and Australia. In any ma...

    Text Solution

    |

  5. The probability that a leap year will have 53 Fridays or 53 Saturday...

    Text Solution

    |

  6. A person write 4 letters and addresses 4 envelopes. If the letters a...

    Text Solution

    |

  7. A speaks truth in 75% cases and B speaks truth in 80% cases. Probabi...

    Text Solution

    |

  8. Three integers are chosen at random from the first 20 integers. The ...

    Text Solution

    |

  9. Out of 30 consecutive integers 2 are chosen at random. The probability...

    Text Solution

    |

  10. A bag contains 5 black balls, 4 white balls and 3 red balls. If a ball...

    Text Solution

    |

  11. Two dice are thrown simultaneously. the probability of getting a pai...

    Text Solution

    |

  12. An urn contains 9 balls two of which are red, three blue and four bl...

    Text Solution

    |

  13. A coin is tossed three times. Event A: two heads appear Event B: last ...

    Text Solution

    |

  14. Five persons entered the lift cabin on the ground floor of an 8 floo...

    Text Solution

    |

  15. A box contains 10 good articles and 6 defective articles. One item i...

    Text Solution

    |

  16. A box contains 6 nails and 10 nuts. Half of the nails and half of th...

    Text Solution

    |

  17. A bag contains 5 brown and 4 white socks. A man pulls out two socks. ...

    Text Solution

    |

  18. If S is the sample space and P(A)=1/3P(B) and S=AuuB ,where A and B ar...

    Text Solution

    |

  19. If A and B are two events, then P(AnnB)=

    Text Solution

    |

  20. If P(AuuB)=0.8 and P(AnnB)=0.3 ,then P(A)+P(B)=

    Text Solution

    |