मराठी

If a and B Are Two Events Such that ( I I I ) P ( a ) = 7 13 , P ( B ) = 9 13 and P ( a ∩ B ) = 4 13 , Then Find P ( a | B ). - Mathematics

Advertisements
Advertisements

प्रश्न

If A and B are two events such that \[ P\left( A \right) = \frac{7}{13}, P\left( B \right) = \frac{9}{13} \text{ and } P\left( A \cap B \right) = \frac{4}{13}, \text{ then find } P\left( \overline{ A }|B \right) . \]

बेरीज

उत्तर

We have  ,
\[P\left( A \right) = \frac{7}{13}, P\left( B \right) = \frac{9}{13} \text{ and }  P\left( A \cap B \right) = \frac{4}{13}\]
\[As, P\left( \overline{ A } \cap B \right) = P\left( B \right) - P\left( A \cap B \right)\]
\[ \Rightarrow P\left( \overline{ A }\cap B \right) = \frac{9}{13} - \frac{4}{13}\]
\[ \Rightarrow P\left( \overline{ A } \cap B \right) = \frac{9 - 4}{13}\]
\[ \Rightarrow P\left(\overline{ A } \cap B \right) = \frac{5}{13}\]
\[\text{ Now } , \]
\[P\left( \overline{ A }|B \right) = \frac{P\left( \overline{ A } \cap B \right)}{P\left( B \right)} = \frac{\left( \frac{5}{13} \right)}{\left( \frac{9}{13} \right)} = \frac{5}{9}\]

shaalaa.com
Probability Examples and Solutions
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 31: Probability - Exercise 31.3 [पृष्ठ ३४]

APPEARS IN

आरडी शर्मा Mathematics [English] Class 12
पाठ 31 Probability
Exercise 31.3 | Q 5.3 | पृष्ठ ३४

संबंधित प्रश्‍न

Ten cards numbered 1 through 10 are placed in a box, mixed up thoroughly and then one card is drawn randomly. If it is known that the number on the drawn card is more than 3, what is the probability that it is an even number?


A coin is tossed three times, if head occurs on first two tosses, find the probability of getting head on third toss.


A die is thrown three times, find the probability that 4 appears on the third toss if it is given that 6 and 5 appear respectively on first two tosses.


Find the chance of drawing 2 white balls in succession from a bag containing 5 red and 7 white balls, the ball first drawn not being replaced.


Two cards are drawn without replacement from a pack of 52 cards. Find the probability that the first is a heart and second is red.


A bag contains 5 white, 7 red and 3 black balls. If three balls are drawn one by one without replacement, find the probability that none is red.


 If P (A) = \[\frac{7}{13}\], P (B) = \[\frac{9}{13}\]  and P (A ∩ B) = \[\frac{4}{13}\], find P (A/B).

 
 
 
 

If A and B are two events such that\[ P\left( A \right) = \frac{6}{11}, P\left( B \right) = \frac{5}{11} \text{ and } P\left( A \cup B \right) = \frac{7}{11}, \text{ then find } P\left( A \cap B \right), P\left( A|B \right) \text { and } P\left( B|A \right) . \]


Two coins are tossed once. Find P (A/B) in each of the following:

A = No tail appears, B = No head appears.


A die is rolled. If the outcome is an odd number, what is the probability that it is prime?

 

A pair of dice is thrown. Find the probability of getting the sum 8 or more, if 4 appears on the first die.


A pair of dice is thrown. Let E be the event that the sum is greater than or equal to 10 and F be the event "5 appears on the first-die". Find P (E/F). If F is the event "5 appears on at least one die", find P (E/F).


A coin is tossed thrice and all the eight outcomes are assumed equally likely. In which of the following cases are the following events A and B are independent?
A = the first throw results in head, B = the last throw results in tail.


A coin is tossed thrice and all the eight outcomes are assumed equally likely. In which of the following cases are the following events A and B are independent?

A = the number of heads is odd, B = the number of tails is odd.


A card is drawn from a pack of 52 cards so the teach card is equally likely to be selected. In which of the following cases are the events A and B independent? 

B = the card drawn is a spade, B = the card drawn in an ace.


A coin is tossed three times. Let the events A, B and C be defined as follows:
A = first toss is head, B = second toss is head, and C = exactly two heads are tossed in a row.
Check the independence of A and B.


A coin is tossed three times. Let the events A, B and C be defined as follows:
A = first toss is head, B = second toss is head, and C = exactly two heads are tossed in a row. B and C .


Given two independent events A and B such that P (A) = 0.3 and P (B) = `0.6. Find P (A ∩ overlineB ) `.


If A and B are two independent events such that P (A ∪ B) = 0.60 and P (A) = 0.2, find P(B).


A die is thrown thrice. Find the probability of getting an odd number at least once.

 

A bag contains 3 red and 5 black balls and a second bag contains 6 red and 4 black balls. A ball is drawn from each bag. Find the probability that one is red and the other is black.


Two balls are drawn at random with replacement from a box containing 10 black and 8 red balls. Find the probability that first ball is black and second is red. 


A bag contains 3 white, 4 red and 5 black balls. Two balls are drawn one after the other, without replacement. What is the probability that one is white and the other is black?

 

A bag contains 4 white, 7 black and 5 red balls. 4 balls are drawn with replacement. What is the probability that at least two are white?

 

X is taking up subjects - Mathematics, Physics and Chemistry in the examination. His probabilities of getting grade A in these subjects are 0.2, 0.3 and 0.5 respectively. Find the probability that he gets
(i) Grade A in all subjects
(ii) Grade A in no subject
(iii) Grade A in two subjects.


A, B and C in order toss a coin. The one to throw a head wins. What are their respective chances of winning assuming that the game may continue indefinitely?


There are 3 red and 5 black balls in bag 'A'; and 2 red and 3 black balls in bag 'B'. One ball is drawn from bag 'A' and two from bag 'B'. Find the probability that out of the 3 balls drawn one is red and 2 are black.

 

Fatima and John appear in an interview for two vacancies for the same post. The probability of Fatima's selection is \[\frac{1}{7}\]  and that of John's selection is \[\frac{1}{5}\] What is the probability that
(i) both of them will be selected?
(ii) only one of them will be selected?
(iii) none of them will be selected?


A bag contains 3 white and 2 black balls and another bag contains 2 white and 4 black balls. One bag is chosen at random. From the selected bag, one ball is drawn. Find the probability that the ball drawn is white.


Three digit numbers are formed with the digits 0, 2, 4, 6 and 8. Write the probability of forming a three digit number with the same digits.


If one ball is drawn at random from each of three boxes containing 3 white and 1 black, 2 white and 2 black, 1 white and 3 black balls, then the probability that 2 white and 1 black balls will be drawn is


Three faces of an ordinary dice are yellow, two faces are red and one face is blue. The dice is rolled 3 times. The probability that yellow red and blue face appear in the first second and third throws respectively, is


The probability that a leap year will have 53 Fridays or 53 Saturdays is


A bag contains 5 black balls, 4 white balls and 3 red balls. If a ball is selected randomwise, the probability that it is black or red ball is


An urn contains 9 balls two of which are red, three blue and four black. Three balls are drawn at random. The probability that they are of the same colour is


Mark the correct alternative in the following question: 

\[\text{ If A and B are two independent events such that}  P\left( A \right) = 0 . 3 \text{ and } P\left( A \cup B \right) = 0 . 5, \text{ then } P\left( A|B \right) - P\left( B|A \right) = \]

 

 


Mark the correct alternative in the following question: A bag contains 5 red and 3 blue balls. If 3 balls are drawn at random without replacement, then the probability that exactly two of the three balls were red, the first ball being red, is


Mark the correct alternative in the following question:
A die is thrown and a card is selected at random from a deck of 52 playing cards. The probability of getting an even number of the die and a spade card is


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×