Subject
Quantitative Aptitude
Topic
Probability
A fair coin is tossed 11 times. What is the probability that only the first two tosses will yield heads ?
A fair coin is tossed 11 times. What is the probability that only the first two tosses will yield heads ?
ক)
(1/2)11খ)
(9)(1/2)গ)
(11C2)(1/2)9ঘ)
(1/2)Explanation
Probability of occurrence of an event, P(E) = Number of favorable outcomes/Numeber of possible outcomes = n(E)/n(S) ⇒ Probability of getting head in one coin = ½, ⇒ Probability of not getting head in one coin = 1- ½ = ½, Hence, All the 11 tosses are independent of each other. ∴ Required probability of getting only 2 times heads =Related questions
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