Answer:
a and c
Step-by-step explanation:
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%
Answer:
2.8a²+0.9a - 1.2
Step-by-step explanation:
Given the expression 0.3(3a-4)-0.05(8a)(-7a)
Expand using the distributive law
0.3(3a-4)-0.05(8a)(-7a)
0.3(3a)-0.3(4)-0.05(8a)(-7a)
0.9a-1.2 - 0.05(8a)(-7a)
0.9a - 1.2 + 2.8a²
Rearrange
2.8a²+0.9a - 1.2
Hence the required expression is 2.8a²+0.9a - 1.2
Answer:
155
Step-by-step explanation:
= (15)x10+5
= 150+5
= 155
According to the question,
Let,
"n" represent the number of miles semir walked.
"y" represent the number of miles sarah walked.
Now, according to the question,
y = 2n - 5 ........................this is your equation
Also,
the question states, each of them collect $18 in pledges for every miles walked.
Given,
Sarah collected $450
Now,
Using unitary method,
Sarah collects $18 for 1 mile
Sarah collects $1 for (1 / $18) mile
Sarah collects $450 for (1 / 18) * 450 mile
= 25 miles
So, Sarah walks 25 miles.
Now,
Taking equation,
y = 2n - 5
Since, y is the no. of miles sarah walked, we can write 25 in place of "y" So,
(25) = 2n - 5
25 + 5 = 2n
30 = 2n
30 / 2 = n
15 = n
Since, "n" is the no. of miles that semir walked, Semir walked 15 miles.
