Question

2. The length of time � necessary to complete a key operation in the construction of houses has an exponential distribution with mean 10 hours a. How long do you expect the key operation to take? b. What is the probability the key operation will take less than 24 hours? c. What is the probability the key operation will take at least 5 hours? d. What is the probability the key operation will take at least an additional 5 hours given the construction works have already worked for 10 hours? e. What do you notice about your answers to part c and part d? What is this property called?

Answer 1

This question has been solved in the attachment I added to the answer. Please try to follow the calculations. If you have any questions you can drop it on the comment section.

a. How long do you expect the key operation to take?

The operation would take 10 minutes

b. What is the probability the key operation will take less than 24 hours

= 0.909285 or 0.909

c. What is the probability the key operation will take at least 5 hours?

= 0.606

d. What is the probability the key operation will take at least an additional 5 hours given the construction works have already worked for 10 hours?

0.6065

e. What do you notice about your answers to part c and part d?

Part c an d have the same values.