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A fair coin tossed repeatedly. If the head appears on first three tosses, then the probability of the tail appearing on the fourth toss equals

A fair coin tossed repeatedly. If the head appears on first three tosses, then the probability of the tail appearing on the fourth toss equals Correct Answer 1/2

Concept:

  • Probability is chance of an event occurring.
  • On tossing a coin, certainty of occurrence of a head (H) or tail (T) on the top

 

Hence, probability of occurrence of head (or tail) = 1/2

Calculation:

Here, a coin tossed repeatedly, but the result of fourth toss is independent of first three tosses.

∴ Probability of the tail appearing on the last (fourth) toss = 1/2

Hence, option (3) is correct.

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