Question

In: Statistics and Probability

We are purchasing a new TV! Let A be the event that the TV was manufactured...

We are purchasing a new TV!

Let A be the event that the TV was manufactured in the U.S., B be the event that the TV has Wifi, and C the event that the customer purchased an extended warranty.

Relevant probabilities are:

P(A) = 0.75

P(B|A) = 0.9

P(B|A′) = 0.8

P(C|A ∩ B) = 0.8

P(C|A ∩ B′) = 0.6

P(C|A′ ∩ B) = 0.7

P(C|A′ ∩ B′) = 0.3

a. What is the probability that the TV was manufactured in the US, with Wifi, and the customer purchased an extended warranty?

b. What is the probability that the TV does NOT have Wifi or the customer did NOT purchase an extended warranty?

c. What is the probability that the customer purchased an extended warranty?

d. What is the probability that the TV does NOT have Wifi given that it was not manufactured in the US?

Solutions

Expert Solution

a)  the probability that the TV was manufactured in the US, with Wifi, and the customer purchased an extended warranty i.e P(A∩B∩C) = ?

By applying duplication rule twice, we will obtain as follows

P(A∩B∩C) = P(C|A∩B)P(A∩B) = P(C|A∩B)P(B|A)P(A) = 0.8×0.9×0.75 = 0.54

the probability that the TV was manufactured in the US, with Wifi, and the customer purchased an extended warranty i.e P(A∩B∩C) = 0.54

b) the probability that the TV does NOT have Wifi or the customer did NOT purchase an extended warranty i.e P( B∩C) = ?

By applying duplication rule,we will obtain as follows

P(B∩C) = P(B∩C∩A)+P(B∩C∩A′)

= P(C|A∩B)P(B|A)P(A) + P(C|A′∩B)P(B/A′)P(A′)

= (0.8×0.9×0.75) + (0.7×0.8×0.25)

= 0.54 + 0.14

= 0.68

the probability that the TV does NOT have Wifi or the customer did NOT purchase an extended warranty i.e P(B∩C) = 0.68

C) the probability that the customer purchased an extended warranty i.e P(C) = ?

P(C) = P(C|A∩B) P(B/A) P(A) + P(C|A∩B′) P(B′/A) P(A) + P(C|A′∩B) P(B/A′) P(A′)  + P(C|A′∩B′) P(B′/A′)P(A′)

  = (0.8×0.9×0.75) +(0.6×0.1×0.75) +(0.7×0.8×0.25) + (0.3×0.2×0.25)

= 0.54 + 0.045 + 0.14 + 0.015

= 0.74

the probability that the customer purchased an extended warranty i.e P(C) = 0.74

d) the probability that the TV does NOT have Wifi given that it was not manufactured in the US i.e P(A|B∩C) = ?

P(A|B∩C) = P(A∩B∩C)/P(B∩C) = 0.54/0.68 = 0.79

the probability that the TV does NOT have Wifi given that it was not manufactured in the US i.e P(A|B∩C) = 0.79


Related Solutions

For customers purchasing a refrigerator at a certain appliance store, let A be the event that...
For customers purchasing a refrigerator at a certain appliance store, let A be the event that the refrigerator was manufactured in the U.S., B be the event that the refrigerator has an icebreaker, and the event that the customer purchased an extended warranty. Relevant probabilities are: P(A) = 0.70 P(B|A) = 0.85 P(B|A ′ ) = 0.75 P(C|A ∩ B) = 0.75 P(C|A ∩ B′ ) = 0.5 P(C|A′ ∩ B) = 0.6 P(C|A′ ∩ B′) = 0.25 b. What...
Let X be the event that the first number is even. Let Y be the event...
Let X be the event that the first number is even. Let Y be the event that the second number is even. Let Z be the event that the sum of the two numbers is even. Are the events X and Z independent? ( Are the events X ∩ Y and Z independent?
Let H be the event of observing a head and T be the event of observing...
Let H be the event of observing a head and T be the event of observing a tail. A balanced coin is tossed three times. (a) List all possible outcomes. (b) List all possible outcomes and find the probabilities of the following events.       A = event exactly two heads are tossed       B = event the first toss is a tail       C = event the first toss is a head       D = event all three tosses come...
Let B={2,4,6} be the event that we roll an even | number. Find P(B) and type...
Let B={2,4,6} be the event that we roll an even | number. Find P(B) and type the fraction
Let P(A)= event that the card selected is a heart, P(B)= event that the card selected...
Let P(A)= event that the card selected is a heart, P(B)= event that the card selected is a club, P(C)= event that the card selected is spade, P(D)= event that the card selected is a diamond, P(E)= even that the card selected is a face card. Find P(A), P(B or D), P(selecting an ace), P(selecting an even digit card or E), P(selecting a red card) P(King of hearts) Create a probability statement and find the theoretical probability.
Let (?,?,?) be a probability space and suppose that ?∈? is an event with ?(?)>0. Prove...
Let (?,?,?) be a probability space and suppose that ?∈? is an event with ?(?)>0. Prove that the function ?:?→[0,1] defined by ?(?)=?(?|?) is a probability on (?,?).
Imagine that you are purchasing small lots of manufactured product. If it is very costly to...
Imagine that you are purchasing small lots of manufactured product. If it is very costly to test a single item, it may be desirable to test a sample of items from the lot instead of testing every item in the lot. Suppose each lot contains 10 items. You decide to sample 3 items per lot and reject the lot if you observe 1 or more defectives. a) If the lot contains 1 defective item, what is the probability that you...
A pair of dice are rolled. Let A be the event as “the first dice roll...
A pair of dice are rolled. Let A be the event as “the first dice roll is 3” and event B as “the second dice roll is 4”. Let event C be as “the sum of the dice rolls are 7.” a) Show that A and B are independent, that A and C are independent, and that B and C are independent. b) Show that A, B, and C are not mutually independent.
Consider randomly selecting a student at a large university, and let "A" be the event that...
Consider randomly selecting a student at a large university, and let "A" be the event that the selected student has a Visa card and "B" be the analogous event for MasterCard. Suppose that P(A)=0.6 and P(B)=0.4. a) Could it be the case that P(A and B)=0.5? Why or why not?
Consider randomly selecting a student at a large university, and let A be the event that...
Consider randomly selecting a student at a large university, and let A be the event that the selected student has a Visa card and B be the analogous event for MasterCard. Suppose thatP(A) = 0.7and P(B) = 0.3. (a)Could it be the case thatP(A ∩ B) = 0.5? Why or why not? (b) From now on, suppose thatP(A ∩ B) = 0.2. What is the probability that the selected student has at least one of these two types of cards?...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT