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:
200.96in^2
Step-by-step explanation:
If the 1st cookie cake is 8" for its diameter and the 2nd cookie cake will have twice the length diameter of the 1st cookie cake .You will do 2 × 8 to get the diameter of the 2nd cookie cake.
First cookie cake diameter is 8".
Second cookie cake's diameter is 16".
Since we need the radius to find the area of the 2nd cookie cake we're going to do 16 / 2 which equals 8 so 8 is the radius.
A=(pi)r^2
A=(pi)8^2 *to the 2nd power means times by the same number
A=(pi)64
A= (3.14)(64)
A=200.96
=200.96^2
pi= 3.14 *for this problem
Answer:
5 meters per minute or 5/1 or 5:1
Answer:
2
Step-by-step explanation:
it literally doubles in size
It would -2 because you have to bring over the -1 on the other side of the equal sign. so you would do -11 plus 1 and you will get -10 then you would 5b÷-10 (simplify).5b=-10
b=-2
