hw3ma540

hw3ma540 - Homework 3 1) Problem 8 Page 228 Suppose that 10...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
MA540 Page | 1 Homework 3 1) Problem 8 Page 228 Suppose that 10 trains arrive independently at a station every day, each at random time between 10:00am and 11:00am. What is the expected number and the variance of those that arrive between 10:15am and 10:28am? Solution: Call a train that arrives between 10:15am and 10:28am a success. Then p , the probability of success is Therefore, the expected value and the variance of the number of trains that arrive in the given period are 2) Problem 9 Page 228 Suppose that a certain bank returns bad checks at a Poisson rate of three per day. What is the probability that this bank returns at most four bad checks during the next two days? Solution: The number of checks returned during next two days is Poisson with . The desired probability is 3) Problem 14 Page 229 Past experience shows that 30% of the customers entering Harry’s Clothing Store will make a purchase. Of the customers who make a purchase, 85% use credit cards. Let X be the number of the next six customers who enter the store, make a purchase, and use a credit card. Find the probability mass function, the expected value, and the variance of X
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 6

hw3ma540 - Homework 3 1) Problem 8 Page 228 Suppose that 10...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online