English

If a and B Are Two Events Such that P (A ∩ B) = 0.32 and P (B) = 0.5, Find P (A/B). - Mathematics

Advertisements
Advertisements

Question

If A and are two events such that P (A ∩ B) = 0.32 and P (B) = 0.5, find P (A/B).

 

Solution

\[\text{ Given } : \]
\[P\left( B \right) = 0 . 5 \]
\[P\left( A \cap B \right) = 0 . 32\]
\[\text{ Now } , \]
\[P\left( \frac{A}{B} \right) = \frac{P\left( A \cap B \right)}{P\left( B \right)}\]
\[ \Rightarrow P\left( \frac{A}{B} \right) = \frac{0 . 32}{0 . 5} = \frac{32}{50} = 0 . 64\]

shaalaa.com
Probability Examples and Solutions
  Is there an error in this question or solution?
Chapter 31: Probability - Exercise 31.3 [Page 34]

APPEARS IN

RD Sharma Mathematics [English] Class 12
Chapter 31 Probability
Exercise 31.3 | Q 3 | Page 34

RELATED QUESTIONS

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 king and the second is an ace.


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.


An urn contains 3 white, 4 red and 5 black balls. Two balls are drawn one by one without replacement. What is the probability that at least one ball is black?


An urn contains 10 black and 5 white balls. Two balls are drawn from the urn one after the other without replacement. What is the probability that both drawn balls are black?

 

A bag contains 4 white, 7 black and 5 red balls. Three balls are drawn one after the other without replacement. Find the probability that the balls drawn are white, black and red respectively.


 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 events such that P (A) = 0.6, P (B) = 0.3 and P (A ∩ B) = 0.2, find P (A/B) and P (B/A).


If A and B are two events such that
\[ P\left( A \right) = \frac{1}{2}, P\left( B \right) = \frac{1}{3} \text{ and }  P\left( A \cap B \right) = \frac{1}{4}, \text{ then find } P\left( A|B \right), P\left( B|A \right), P\left( \overline{ A }|B \right) \text{ and }  P\left( \overline{ A }|\overline{ B } \right) .\]


If P (A) = \[\frac{6}{11},\]  P (B) = \[\frac{5}{11}\]  and P (A ∪ B) = \[\frac{7}{11},\]  find

(i) P (A ∩ B)
(ii) P (A/B)
(iii) P (B/A)

A die is thrown twice and the sum of the numbers appearing is observed to be 8. What is the conditional probability that the number 5 has appeared at least once?


Two dice are thrown and it is known that the first die shows a 6. Find the probability that the sum of the numbers showing on two dice is 7.


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 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 three times. Let the events AB 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. C and A


If A and B be two events such that P (A) = 1/4, P (B) = 1/3 and P (A ∪ B) = 1/2, show that A and B are independent events.


A bag contains 3 red and 2 black balls. One ball is drawn from it at random. Its colour is noted and then it is put back in the bag. A second draw is made and the same procedure is repeated. Find the probability of drawing (i) two red balls, (ii) two black balls, (iii) first red and second black ball.


An urn contains 4 red and 7 black balls. Two balls are drawn at random with replacement. Find the probability of getting 2 red balls.  


An urn contains 4 red and 7 black balls. Two balls are drawn at random with replacement. Find the probability of getting 2 blue balls. 


Let A and B be two independent events such that P(A) = p1 and P(B) = p2. Describe in words the events whose probabilities are:  `1 - (1 - p_1 )(1 -p_2 ) `


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. 


In a family, the husband tells a lie in 30% cases and the wife in 35% cases. Find the probability that both contradict each other on the same fact.

 

A husband and wife appear in an interview for two vacancies for the same post. The probability of husband's selection is 1/7 and that of wife's selection is 1/5. What is the probability that none of them will be selected?

 

 


A and B take turns in throwing two dice, the first to throw 10 being awarded the prize, show that if A has the first throw, their chance of winning are in the ratio 12 : 11.


When three dice are thrown, write the probability of getting 4 or 5 on each of the dice simultaneously.

 

If A and B are two independent events such that P (A) = 0.3 and P (A ∪ \[B\]) = 0.8. Find P (B).

 
 

If ABC are mutually exclusive and exhaustive events associated to a random experiment, then write the value of P (A) + P (B) + P (C).


If A and B are two independent events, then write P (A ∩ \[B\] ) in terms of P (A) and P (B).

 
 

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


A person writes 4 letters and addresses 4 envelopes. If the letters are placed in the envelopes at random, then the probability that all letters are not placed in the right envelopes, is


Out of 30 consecutive integers, 2 are chosen at random. The probability that their sum is odd, is


A box contains 6 nails and 10 nuts. Half of the nails and half of the nuts are rusted. If one item is chosen at random, the probability that it is rusted or is a nail is


If S is the sample space and P (A) = \[\frac{1}{3}\]P (B) and S = A ∪ B, where A and B are two mutually exclusive events, then P (A) =


If P (A ∪ B) = 0.8 and P (A ∩ B) = 0.3, then P \[\left( A \right)\] \[\left( A \right)\] + P \[\left( B \right)\] =


Mark the correct alternative in the following question:

\[\text{ If A and B are two events such that } P\left( A \right) = \frac{1}{2}, P\left( B \right) = \frac{1}{3}, P\left( A|B \right) = \frac{1}{4}, \text{ then } P\left( A \cap B \right) \text{ equals} \]


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:

\[\text{ If A and B are two events such that } P\left( A|B \right) = p, P\left( A \right) = p, P\left( B \right) = \frac{1}{3} \text{ and } P\left( A \cup B \right) = \frac{5}{9}, \text{ then} p = \]


A coin is tossed 5 times. Find the probability of getting (i) at least 4 heads, and (ii) at most 4  heads. 


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×