Answer:
The probability is 0.0428
Step-by-step explanation:
First, let's remember that the binomial distribution is given by the formula:
![P(X=k) =\left[\begin{array}{ccc}n\\k\end{array}\right] p^{k}(1-p)^{n-k}](https://tex.z-dn.net/?f=P%28X%3Dk%29%20%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Dn%5C%5Ck%5Cend%7Barray%7D%5Cright%5D%20p%5E%7Bk%7D%281-p%29%5E%7Bn-k%7D)
where k is the number of successes in n trials and p is the probability of success.
However, the problem tells us that when there isn't a number of trials fixed, we can use the geometric distribution and the formula for getting the first success on the xth trial becomes:
The problem asks us to find the probability of the first success on the 4th trial (given that the first subject to be a universal blood donor will be the fourth person selected)
Using this formula with the parameters given, we have:
p = 0.05
x = 4
Substituting these parameters in the formula and solving it, we get:
Therefore, the probability that the first subject to be a universal blood donor is the fourth person selected is 0.0428 or 4.28%
9514 1404 393
Answer:
x = -6
Step-by-step explanation:
A plot of the points tells you one is above the other on the same vertical line. The equation for a vertical line is ...
x = constant
In order for the line to go through points that have x-coordinates of -6, the constant must be -6. The equation of the line is ...
x = -6
Answer:
Step-by-step explanation: X and Y represent the digits.
The tens digit is twice the units digit.
The digit in the Tens place has 10× its base value, so we can set up equations to model the information given.
10x +y 10y +x are Original & Reversed numbers
X = 2y means the Tens digits is twice the units digit.
10y + x +2 = 10x +y - 34 models the statement: The reversed number plus two is 34 less than the original number.
Substitute 2y for x to solve for y
10y +2y +2= 10(2y) + y -34
Distribute and combine like terms
12y + 2 = 20y +y - 34
34 +2 = 21y -12y
36 = 9y Divide both sides to find the value of y.
4 = y
X = 2(4) Substitute 4 for y to find x
X = 8
Original number: 84 Reversed number: 48
Substitute into equation model
48 +2= 84 -34
50 = 50
True!
