Question

15 A tire company produced a batch of 6,500 tires that includes exactly 240 that are defective.

a. If 4 tires are randomly selected for installation on a​ car, what is the probability that they are all​ good?

b. If 100 tires are randomly selected for shipment to an​ outlet, what is the probability that they are all​ good? Should this outlet plan to deal with defective tires returned by​ consumers?

16.

Refer to the figure below in which surge protectors p and q are used to protect an expensive​high-definition television. If there is a surge in the​ voltage, the surge protector reduces it to a safe level. Assume that each surge protector has a 0.95 probability of working correctly when a voltage surge occurs. Complete parts​ (a) through​ (c) below.

a. If the two surge protectors are arranged in​ series, what is the probability that a voltage surge will not damage the​ television?

____ ​(Do not​ round.)

b. If the two surge protectors are arranged in​ parallel, what is the probability that a voltage surge will not damage the​ television?

Answer 1

15)

a)
probability that all 4 are good = 240C4 /6500C4
= (240 * 239*238*237)/(6500*6499 * 6498*6497)
= 0.00000181418

b)

probability that all 100 are good = 240C100/6500C100