Let X denote the number of brand X VCRs sold during a particular week by a certain store. The pmf of X is x 0 1 2 3 4 .1 .2 .3 .25 .15 Seventy percent of all customers who purchase brand X VCRs also buy an extended warranty. Let Y denote the number of purchasers during this week who buy an extended warranty. a. What is P(X = 4, Y = 2)? [Hint: This probability equals P(Y = 2/X = 4) ⋅ P(X = 4); now think of the four purchases as four trials of a binomial experiment, with success on a trial corresponding to buying an extended warranty.]b. Calculate P(X =Y).c. Determine the joint pmf of X and Y and then the marginal pmf of Y.

What values of data might affect the statistical measures of spread and center

James wants to promote his band on the internet. site a offers website hosting for $4.95 per month with a $49.95 startup fee. site b offers website hosting for $9.95 per month with no startup fee. for how many months would james need to keep the website for site a to be a better choice than site b? 1. define a variable for the situation. 2. write an inequality that represents the situation. 3.solve the inequality to find out how many months he needs to keep the website for site a to be less expensive than site b. 4. using words, describe how many months he needs to keep the website for site a to be less expensive than site b.

Which is the solution to the inequality? 2 3/52 1/15 b< 3 2/15 b> 3 2/15