Respuesta :
Answer:
a) 26.79%, b) 50.42% and c) 22.79%
Step-by-step explanation:
a. What is the probability that both Dave and Mike will show up?
As decisions of showing up can be assumed to be independent, the probability will be given by
[tex](1-0.53)(1-0.43)=(0.47)(0.57)=0.2679[/tex]=26.79%
b. What is the probability that at least one of them will show up?
There are two possibilities for this to happen:
- Dave shows up but Mike does not. The probability of Dave to show up is (1-0.53)=0.47 and the probability that Mike does not is 0.43. Then, as these events are independent, the probability for both of them to happen is (0.47)(0.43)=0.2021=20.21%
- Mike shows up but Dave does not. The probability of Mike to show up is (1-0.43)=0.57 and the probability that Mike does not is 0.53. Then, as these events are independent, the probability for both of them to happen is (0.57)(0.53)=0.3021=30.21%
Therefore, the probability that at least one of them will show up? is 20.21%+30.21%=50.42%.
c. What is the probability that neither Dave nor Mike will show up?
As decisions of showing up can be assumed to be independent, the probability will be given by
[tex](0.53)(0.43)=0.2279[/tex]=22.79%
Probability of an event is the measure of its chance of occurrence. The probabilities for Dave and Mike showing up are:
- P(Dave and Mike both will show up) = 0.2679 = 26.79%
- P(At least one of them will show up) = 0.7721 = 77.21%
How to convert percent to probability?
Percent counts the number compared to 100 whereas probability counts it compare to 1.
So, if we have a%, that means for each 100, there are 'a' parts. If we divide each of them with 100, we get:
For each 1, there are a/100 parts.
Thus, 50% = 50/100 = 0.50 (in probability)
What is the addition rule of probability for two events?
For two events A and B, we have:
Probability that event A or B occurs = Probability that event A occurs + Probability that event B occurs - Probability that both the event A and B occur simultaneously.
This can be written symbolically as:
[tex]P(A \cup B) = P(A) + P(B) - P(A \cap B)[/tex]
Let for the given condition, the events be
- A = Dave will show up
- A' = Dave won't show up (complement event of A)
- B = Mike will show up
- B' = Mike won't show up (complement event of event B)
Then, by the given data, we have the probabilities as:
- P(A') = 53% = 0.53
- P(A) = 1-P(A) = 1-0.53 = 0.47
- P(B') = 43% = 0.43
- P(B) = 1 - 0.43 = 0.57
The needed probabilities are calculated as:
Case 1: P(Dave and Mike both will show up)
P(Dave and Mike both will show up) = P(A ∩ B)
Since it is given that A' and B' (and thus A and B) are independent of each other.
This means
P(A ∩ B) = P(A)P(B) (by definition of independent events)
Thus, P(A ∩ B) = 0.47 × 0.57 = 0.2679
Case 2: P(At least one of them will show up)
P(At least one of them will show up) = P(A∪B)
Using the addition rule of probability for two events, we get:
P(A∪B) = P(A) - P(B) - P(A ∩ B) = 0.47 + 0.57 - 0.2679 = 0.7721
Thus, the probabilities for Dave and Mike showing up are:
- P(Dave and Mike both will show up) = 0.2679 = 26.79%
- P(At least one of them will show up) = 0.7721 = 77.21%
Learn more about probability here:
brainly.com/question/1210781