There are `n` letters and `n` addressed envelopes. Find the probability that all the letters are not kept in the right envelope.
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Gita said that the probability of impossible event is 1. Pravallika said that probability of sure event is 0 and Atiya said that the probability
Correct option is: C) Atiya \(\because\) Probability of an impossible event is 0 \(\neq\) 1. Hence, the statement of Gita is wrong. Also, probability of a sure event is 1 \(\neq\) 0 Hence, the statement of Pravallika is wrong. Since, 0 \(\leq\) P \(\leq\) 1,...
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Gita said that the probability of impossible event is 1. Pravallika said that probability of sure event is 0 and Atiya said that the probability
2 Answers
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Probability that A speaks truth is `4/5` . A coin is tossed. A reports that a appears. The probability that actually there was head is
Correct Answer - A Let `E_(1)=` event of getting head, `E_(2)=` event of not getting head, and `E=` event that A tells, a head is obtained `:.P(E_(1))=P(E_(2))=1/2``P(E//E_(1))=` probability that A tells...
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If the letters of the word REGULATIONS be arranged at random, find the probability that there will be exactly four letters between the `R` and the`Edo
Correct Answer - `(11!)/(.^(9)P_(4)xx6! xx 2!)` Total number of ways of arranging 11 letters is (11)! The number of selection of 4 letters to be placed between R and E from...
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There are eight girls among whom two are sisters, all of them are t sit on a round table. Find the probability that the two sisters do not sit togethe
Correct Answer - `(5)/(7)` Total number of ways is `7!` Favorable number of ways is `7! - 2 (6!)`. Hence, the probability is `(7! - 2(6!))/(7!) = 1 - (2)/(7) =...
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There are 10 prizes, five As, there Bs and two Cs, placed in identical sealed envelopes for the top 10 contestants in a mathematics contest. The prize
Correct Answer - A `n(S) = .^(10)C_(7) = 120` `n(E) = .^(5)C_(4) xx .^(3)C_(2) xx .^(2)C_(1)` `therefore P(E) = (5xx3xx2)/(120) = (1)/(4)`
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Suppose that 90% of people are right-handed. What is the probability that at most 6 of a random sample of 10 people are right-handed?
A person can be either right-handed or left-hended. It is given that `90%` of the people are right-handed. Therefore, `p=P("right-handed")=9/10` `q=P("left-handed")=1-9/10=1/10` Using binomial distribution, the probability that at most six...
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A man takes a step forward with probability 0.4 and backward with probability 0.6. Find the probability that at the end of 5 steps, he is one step awa
The man can be one stap away from the statting point if (i) either he is one stgep aheld or (ii) one step behind the starting point. Now if at...
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Probability that A speaks truth is `4/5` . A coin is tossed. A reports that a appears. The probability that actually there was head is (A) `4/5` (B)`1
Correct Answer - `4//5` Let `E_(1) and E_(2)` be the events such that `E_(1): ` A speaks truth `E_(2):` A speaks false m Let X be the event that a head appears....
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The probability of event `A` is `3//4`. The probability of event `B`, given that event `A` occurs is `1//4`. The probability of event `A`, given that
Correct Answer - C `(c )` `P(A)=(3)/(4)`, `P(B//A)=(1)/(4)` `P(A//B)=(2)/(3)` `P(B//A)=(P(BnnA))/(P(A))=(1)/(4)` (given) `:.P(BnnA)=(3)/(4)*(1)/(4)=(3)/(16)` Now `P(A//B)=(P(AnnB))/(P(B))=(2)/(3)`(given) `:.P(B)=(3)/(2)*(3)/(16)=(9)/(32)` `:. P(AuuB)=(3)/(4)+(9)/(32)-(3)/(16)=(24+9-6)/(32)=(27)/(32)` `:. P(A^(C )nnB^(C ))=1-P(AuuB)=1-(27)/(32)=(5)/(32)`
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