As you said, if the probability of success for each individual trial is 50%, then the probability of at least one being successful is 93.75%
Probability that all four trials are successful = (0.5 * 0.5 * 0.5 * 0.5) = 6.25% Probability that at least one is successful = 100% - (0.5 * 0.5 * 0.5 * 0.5) = 93.75%
Let's have some fun here and bump up the success probability to 70% based on the fact that variations of these concoctions have been proven successful in less formal settings:-
Probability that all four trials are successful = (0.70 * 0.70 * 0.70 * 0.70) = 24.01% Probability that at least one is successful = 100% - (0.3 * 0.3 * 0.3 * 0.3) = 99.19%
I think I prefer that one
IHL Price at posting:
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