If copies of all your computer data are stored on four independent hard disk​ drives, what is the probability that during a​ year, you can avoid catastrophe with at least one working​ drive? With four hard disk​ drives, the probability that catastrophe can be avoided is

Step-by-step explanation:

Given

--- rate of hard disk drives failure

--- number of hard disk drives

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Required

First, calculate the probability that the none of the 4 selected is working;

Using the complement rule, the probability that at least 1 is working is:

This gives:

answer: are you

step-by-step explanation: