Answer:
The probability is 0.0428
Step-by-step explanation:
First, let's remember that the binomial distribution is given by the formula:
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%
Step-by-step explanation:
Find the Center and Radius (x-4)^2+y^2=4
(
x
−
4
)
2
+
y
2
=
4
This is the form of a circle. Use this form to determine the center and radius of the circle.
(
x
−
h
)
2
+
(
y
−
k
)
2
=
r
2
Match the values in this circle to those of the standard form. The variable
r
represents the radius of the circle,
h
represents the x-offset from the origin, and
k
represents the y-offset from origin.
r
=
2
h
=
4
k
=
0
The center of the circle is found at
(
h
,
k
)
.
Center:
(
4
Answer:
Yes, you are right. Great job!
Step-by-step explanation:
Answer:
Equation: 
Solution: 
Step-by-step explanation:
Let be "t" the number of movie tickets bought by the group of friends.
According to the information given in the exercise, the price of each movie ticket is: $8.50.
Then, you can represent the amount (in dollars) the group of friends spent in movie tickets, with this expression:

You know that one person spent $6.50, then the expression that represents the total amount (in dollars) the group of friends spent in food and movie tickets, is:

Since that total amount spent is given in the exercise, you can write the following equation to determine how many tickets were bought:

Finally, you can solve for "t" in order to find the solution of the equation. This is:

Answer:
-31 1/3
Step-by-step explanation:
17-3(x+9)=50
-17 -17
-3(x+9)=67
divide by -3
x+9=-22 1/3
-9 -9
x=-31 1/3