A community for students.
Here's the question you clicked on:
 0 viewing
anonymous
 3 years ago
The durations of phone calls taken by the receptionist at an office are like draws made at random with replacement from a list that has an average of 8.5 minutes (that's 8 minutes and 30 seconds) and an SD of 3 minutes. Approximately what is the chance that the total duration of the next 100 calls is more than 15 hours?
anonymous
 3 years ago
The durations of phone calls taken by the receptionist at an office are like draws made at random with replacement from a list that has an average of 8.5 minutes (that's 8 minutes and 30 seconds) and an SD of 3 minutes. Approximately what is the chance that the total duration of the next 100 calls is more than 15 hours?

This Question is Closed

kropot72
 3 years ago
Best ResponseYou've already chosen the best response.0\[X=\frac{15\times 60}{100}=9\ minutes\] \[z=\frac{X\mu}{\sigma}=\frac{98.5}{3}=0.1667\] Reference to a standard normal distribution table shows that the cumulative probability of calls averaging less than 9 minutes is 0.5662. Therefore the chance that the total duration of the next 100 calls is more than 15 hours is 1.0000  0.5662

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0@kropot72 that's incorrect , thnx
Ask your own question
Sign UpFind more explanations on OpenStudy
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.