Question

Sam is a representative who sells large appliances such as refrigerators, stoves, and so forth. Let x be the number of appliances Sam sells on a given day. And let f be the number of days (frequency) with which he sells x appliances. For a random sample of 240 days, Sam had the following sales record

x 1 2 3 4 5 6 7

f 14 72 ? 41 28 14 8

Assume the sales record is representative of the population of all sales days: (a) Use relative frequency to find P(x) for each x from 0 to 7. (b) Use a histogram to graph the probability distribution of part (a). (c) Compute the probability that x is between 2 and 5 (including 2 and 5). (d) Compute the probability that x is less than 3. (e) Compute the expected value of the x distribution. (f) NOT REQUIRED (longer question) Compute the standard deviation of the x distribution.

Answer 1