This probability problem is for my calculus class....(adsbygoogle = window.adsbygoogle || []).push({});

a) A type of lightbulb is labeled as having an average lifetime of 1000 hours. It's reasonable to model the probability of failure of these bulbs by an exponential density function with mean = 1000. Use this model to find the probability that a bulb

(i) fails within the first 200 hours

(ii) burns for more than 800 hours

b) What is the median lifetime of these lightbulbs?

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# Probability and lifetime of a lightbulb

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