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In Problem 21, find d so that the probability of a randomly selected microwave oven lasting d years or less is .8.
21. The life expectancy (in years) of a microwave oven is a continuous random variable with probability density function
- (A) Find the probability that a randomly selected microwave oven lasts at most 6 years.
- (B) Find the probability that a randomly selected microwave oven lasts from 6 to 12 years.
- (C) Graph y = f(x) for [0, 12] and show the shaded region for part (A).
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