It is known that the lifetime of a certain brand of car batteries is exponentially distributed with an average of 4 years. An automaker needs the batteries that you use on your vehicles last at least 4 years so that your profit is not harmed. If the automaker used batteries of that brand, what is the probability that a given battery does not harm if it has survived 3 years? 0.075 (b) 0.472 (c) 0.676 (d) 0.221 (e) 0.779
Added by Albert W.
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Step 1: Given that the lifetime of the car batteries is exponentially distributed with an average of 4 years, the probability density function f(x) can be written as \( f(x) = \frac{1}{4}e^{-\frac{x}{4}} \). Show more…
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