Question

A letter is known to have come from either TATANAGAR or CALCUTTA. On the envelope, just two consecutive letters, TA, are visible. The probability that the letter has come from CACUTTA is

Solution

Correct option is

4/11

Let E1 denote the event that the letter came from TATANAGAR and E2the event that the letter came from CALCUTTA. Let A denote the event that the two consecutive alphabets visible on the envelope are TA. We have P(E1) = 1/2, P(E2) = 1/2,

 Therefore, by Bayes’ theorem we have

                        

SIMILAR QUESTIONS

Q1

Each of two persons A and B toss three fair coins. The probability that both get the same number of heads is

Q2

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Q3

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Q4

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Q5

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Q6

An experiment has 10 equally likely outcomes. Let A and B two non – empty events of the experiment. If a consists of 4 outcomes, the number of outcomes that B must have so that A and B are independent, is

Q7

If AB and C are the events such that P(B) = 3/4, P(A ∩ B ∩ C’) = 1/3P(A’ ∩ B ∩ C’) = 1/3, then P (B ∩ C) is equal to

Q8

A fair coin is tossed n times. If the probability that head occurs 6 times is equal to the probability that occurs 8 times, then value of n is

Q9

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

Q10

A group of 6 boys and 6 girls is randomly divided into two equal groups. The probability that each group contains 3 boys and 3 girls is