Bunuel wrote:

In nine independent trials, what is the probability that Outcome A happens at least once?

(1) The probability that Outcome A does not happen even once in any of the nine trials is 0.026

(2) the probability of Outcome A resulting in a single trial is 1/3.

Kudos for a correct solution.

Probability of Favorable Outcome + Probability of Unfavorable Outcome = 1

i.e. Probability of Favorable Outcome = 1 - Probability of Unfavorable Outcomei.e. probability that Outcome A happens at least once = 1 - Probability that Outcome A never happensStatement 1: P (A never happens) = 0.026i.e. P (A happens atleast once) = 1- 0.026 = 0.974

SUFFICIENT

Statement 2: probability of Outcome A resulting in a single trial is 1/3i.e. probability of Outcome A Not happen in a single trial is 1-(1/3) = 2/3

i.e. Outcome A never happens in all 9 trials = (2/3)^9 = 0.026

i.e. P (A happens atleast once) = 1- 0.026 = 0.974

SUFFICIENT

Answer: Option

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