testing header
Math Goodies is a free math help portal for students, teachers, and parents.
Free Math
Newsletter
 
 
Interactive Math Goodies Software

Buy Math Goodies Software
testing left nav
Math Forums @ Math Goodies
Math Forums @ Math Goodies
Home | Profile | Register | Active Topics | Members | Search | FAQ
Username:
Password:
Save Password
Forgot your Password?

 All Forums
 Homework Help Forums
 Probability and Statistics
 Probability Question
 New Topic  Topic Locked
 Printer Friendly
Author Previous Topic Topic Next Topic  

sp00ky
Average Member

Canada
7 Posts

Posted - 10/06/2007 :  00:10:00  Show Profile
Hi,
I am having a real hard time answering this question and I was wondering if someone can give me some pointers and how to solve this problem:

The probability that an Avon salesperson makes a sale to a prospective client on the first visit is 0.4. If the sale is not made on the first visit, the probability that it will be made on the second visit is 0.65. A prospective client is never visited more than twice if no sale is made. What is the probability that the salesperson will make a sale to a prospective client?

At first I thought you just multiply 0.4 by 0.65 but the answer seems way too low. Also, I thought it would be 0.4+0.65/(1-0.4)+(1-0.65) might be the answer but it was over 1 so I know that's not right. So if someone can help me out, that would be really appreciated =)

Thank you
Go to Top of Page

tkhunny
Advanced Member

USA
1001 Posts

Posted - 10/06/2007 :  01:22:36  Show Profile
0.4*0.65 would be the probability of making a sale BOTH times, except that the second trip wouldn't be made.

You can calculate it directly.

A sale on the second try REQUIRES failure on the first. Pr(Failure on the first) = 1 - 0.4 = 0.6

0.4 + 0.6*0.65

You can calculate it from the back door.
Pr(making a sale) = 1 - Pr(NOT making a sale)

1 - 0.6*0.35

You can construct a nice tree:

Sale1 0.4

NoSale1 0.6
-----Sale2 0.65
-----NoSale2 0.35

Total Probability

Sale1 0.4
NoSale1Sale2 0.6*0.65
NoSale1NoSale2 0.6*0.35
Go to Top of Page
  Previous Topic Topic Next Topic  
 New Topic  Topic Locked
 Printer Friendly
Jump To:
Math Forums @ Math Goodies © 2000-2004 Snitz Communications Go To Top Of Page
This page was generated in 0.13 seconds. Snitz Forums 2000
testing footer
About Us | Contact Us | Advertise with Us | Facebook | Blog | Recommend This Page




Copyright © 1998-2014 Mrs. Glosser's Math Goodies. All Rights Reserved.

A Hotchalk/Glam Partner Site - Last Modified 15 Oct 2014