Question 1136552
the probability that at least one is successful is equal to the 1 minus the probability that none are successful.


the probability that none are successful is equal to (1 - .9) * (1 - .75) * (1 - .60) = .1 * .25 * .4 = .01


the probability that at least one will be successful is therefore 1 - .01 = .99.


i used excel to detail all the possible probabilities.


it is shown below.


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