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MHT CET202615 April 2026Evening ShiftMathematicsProbabilityActual

The probability that event A happens in a trial is 0.4. If three independent trials are made, then the probability that A happens at least once is.......

Options

  1. A0.216
  2. B0.926
  3. C0.064
  4. D0.784

Correct answer

D. 0.784

Step-by-step solution

Let P(A) be the probability that event A happens in a single trial. P(A) = 0.4 The probability that event A does not happen in a single trial is P(A') = 1 - 0.4 = 0.6 . Since the trials are independent, the probability that A does not happen in any of the three trials is (P(A'))^3 = (0.6)^3 = 0.216 . The probability that A happens at least once in three trials is 1 - P( A does not happen in any trial ) . 1 - 0.216 = 0.784 Answer: 0.784

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