Question

An electronics store has received a shipment of 25 table radios that have connections for an iPod or iPhone. Ten of these have two slots (so they can accommodate both devices), and the other fifteen have a single slot. Suppose that eight of the 25 radios are randomly selected to be stored under a shelf where the radios are displayed, and the remaining ones are placed in a storeroom. Let X = the number among the radios stored under the display shelf that have two slots.

(a) What kind of distribution does X have (name and values of all parameters)?

hypergeometric with N = 10, M = 8, and n = 10

binomial with n = 10, x = 8, and p = 8/10

hypergeometric with N = 25, M = 10, and n = 8

binomial with n = 25, x = 10, and p = 8/25

(b) Compute

P(X = 2), P(X ≤ 2), and P(X ≥ 2).

(Round your answers to four decimal places.)

P(X = 2) =
P(X ≤ 2) =
P(X ≥ 2) =

(c) Calculate the mean value and standard deviation of X. (Round your standard deviation to two decimal places.)

mean value	radios
standard deviation	radios

Answer 1