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प्रश्न
Examine the following statement and comment:
If two coins are tossed at the same time, there are 3 possible outcomes—two heads,
two tails, or one of each. Therefore, for each outcome, the probability of occurrence
is 1/3
उत्तर
Given statement is incorrect. If 2 coins are tossed at the same time,
Total no. of possible outcomes = 4 {HH, HT, TH, TT}
P(HH) = P(HT) = P(TH) = P(TT) =1/4 {∵ Probability =`"No.of favorable outcomes"/"'Total no.of possible outcomes"`}
I.e. for each outcome, probability of occurrence is 1/4
Outcomes can be classified as (2H, 2T, 1H & 1T) P(2H) =1/4 , P(2T) =1/4, P(1H & HT) =2/4
Events are not equally likely because the event ‘one head & 1 tail’ is twice as likely
to occur as remaining two.
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