Answer:
0.674
Step-by-step explanation:
If the random variable X is exponentially distributed and X has an average value of 25 minutes, then its probability density function (PDF) is
and its cumulative distribution function (CDF) is
So, <em>the probability that X is less than 28 minutes is
</em>

Answer:
A
Step-by-step explanation:
Answer:
15
Step-by-step explanation:
3/5 = wooden
2/5 = mechanical
Step-by-step explanation:
about 7% (not exactly 7%, just about)