Answer:
a) 0.2416
b) 0.4172
c) 0.0253
Step-by-step explanation:
Since the result of the test should be independent of the time , then the that the test number of times that test proves correct is independent of the days the river is correct .
denoting event a A=the test proves correct and B=the river is polluted
a) the test indicates pollution when
- the river is polluted and the test is correct
- the river is not polluted and the test fails
then
P(test indicates pollution)= P(A)*P(B)+ (1-P(A))*(1-P(B)) = 0.12*0.84+0.88*0.16 = 0.2416
b) according to Bayes
P(A∩B)= P(A/B)*P(B) → P(A/B)=P(A∩B)/P(B)
then
P(pollution exists/test indicates pollution)=P(A∩B)/P(B) = 0.84*0.12 / 0.2416 = 0.4172
c) since
P(test indicates no pollution)= P(A)*(1-P(B))+ (1-P(A))*P(B) = 0.84*0.88+ 0.16*0.12 = 0.7584
the rate of false positives is
P(river is polluted/test indicates no pollution) = 0.12*0.16 / 0.7584 = 0.0253
Answer is <
Why? 1/4 is smaller than 1/2
1/4 can be 4 slices while 1/2 can be 2 slices
2 slices > 4 slices
Answer:
5/12
7/12
125/36 = 3,47%
50/11 = 4,54%
Step-by-step explanation:
Probability a black sock is selected when a person chooses 1 sock = 5/12
Probability a white or brown sock is selected when a person chooses 1 sock =
7/12
Probability a person chooses 3 socks and selects a white first, a black second, and a brown last if the socks are replace = (4/12 * 5/12 * 3/12)*100 =125/36 = 3,47%
Pobability a person chooses 3 socks and selects a white first, a black second, and a brown last if the socks are NOT replace = (4/12 * 5/11 * 3/ 10)*100 = 50/11 = 4,54%
D. Since we know that 1 ticket = $8 we would multiply to figure out how much 7 tickets were. (7x$8). And to figure out his change you would subtract the ticket amount from $100 :) Hope this helps
Answer:
Suppose we roll a six-sided number cube. Rolling a number cube is an example of an experiment, or an activity with an observable result. The numbers on the cube are possible results, or outcomes, of this experiment. The set of all possible outcomes of an experiment is called the sample space of the experiment. The sample space for this experiment is \displaystyle \left\{1,2,3,4,5,6\right\}{1,2,3,4,5,6}. An event is any subset of a sample space.
The likelihood of an event is known as probability. The probability of an event \displaystyle pp is a number that always satisfies \displaystyle 0\le p\le 10≤p≤1, where 0 indicates an impossible event and 1 indicates a certain event. A probability model is a mathematical description of an experiment listing all possible outcomes and their associated probabilities. For instance, if there is a 1% chance of winning a raffle and a 99% chance of losing the raffle, a probability model would look much like the table below.
Outcome Probability
Winning the raffle 1%
Losing the raffle 99%
The sum of the probabilities listed in a probability model must equal 1, or 100%.
