Answer:
a) We need a sample size of at least 705.
b) We need a sample size of at least 1692.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of 
, and a confidence level of 
, we have the following confidence interval of proportions.
In which
z is the zscore that has a pvalue of 
.
The margin of error is:
90% confidence level
So 
, z is the value of Z that has a pvalue of 
, so 
.
a) If she uses 1999 estimate of 11.8% obtained from the Current Population Survey.
We need a sample of size at least n
n is found when 
.
So
Rounding up
We need a sample size of at least 705.
b) She does not use any estimate.
Same thing as above, we just use 
when do not use any estimate.
Rounding up
We need a sample size of at least 1692.
I'm assuming you want to simplify the expression since it's not equal to anything.. you can't solve for "a" unless it's equal to something.
factor
8a³ - 2a²+ 12a - 3
2a²(4a - 1) + 3(4a -1)
(4a - 1) is a like term that can be combined further.
(2a² + 3)(4a - 1)
So,
x + y = 117
y = x + 1
x + x + 1 = 117
Collect Like Terms
2x + 1 = 117
Subtract 1 from both sides
2x = 116
Divide both sides by 2
x = 58
y = x + 1
y = 58 + 1
y = 59
The 2 consecutive integers are 58 and 59.
Answer:
Step-by-step explanation:
The equation of a circle in standard form:
(h, k) - center
r - radius
1. We have the equation:
<h2 />
2. We have the center (-4, 3) and the radius r = 6. Substitute:
3. We have the endpoints of the diameter: (-1, 6) and (5, -4).
Midpoint of diameter is a center of a circle.
The formula of a midpoint:
Substitute:
The center is in (2, 1).
The radius length is equal to the distance between the center of the circle and the endpoint of the diameter.
The formula of a distance between two points:
Substitute the coordinates of the points (2, 1) and (5, -4):
Finally we have:
