Answer:
The lower confidence limit of the 95% confidence interval for the population proportion of Americans who were victims of identity theft is 0.0275.
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 z-score that has a p-value of 
.
A 2003 survey showed that 14 out of 250 Americans surveyed had suffered some kind of identity theft in the past 12 months.
This means that 
95% confidence level
So 
, z is the value of Z that has a p-value of 
, so 
.
The lower limit of this interval is:
The lower confidence limit of the 95% confidence interval for the population proportion of Americans who were victims of identity theft is 0.0275.
Answer:
Step-by-step explanation:
breadth = x
length = 2x
Perimeter = 540m
2*( length + breadth ) = 540
2 *(2x + x) = 540
3x = 540/2
3x = 270
x = 270/3
x = 90 m
Breadth = 90m = 90 *100 = 9000 cm
Length = 2*90 = 180 m = 180 * 100 = 18000 cm
No.of bricks = Area of room/ area of one brick
= 9000 * 18000 / 20 * 12
= 675000 bricks
<span>n = 5
The formula for the confidence interval (CI) is
CI = m ± z*d/sqrt(n)
where
CI = confidence interval
m = mean
z = z value in standard normal table for desired confidence
n = number of samples
Since we want a 95% confidence interval, we need to divide that in half to get
95/2 = 47.5
Looking up 0.475 in a standard normal table gives us a z value of 1.96
Since we want the margin of error to be ± 0.0001, we want the expression ± z*d/sqrt(n) to also be ± 0.0001. And to simplify things, we can omit the ± and use the formula
0.0001 = z*d/sqrt(n)
Substitute the value z that we looked up, and get
0.0001 = 1.96*d/sqrt(n)
Substitute the standard deviation that we were given and
0.0001 = 1.96*0.001/sqrt(n)
0.0001 = 0.00196/sqrt(n)
Solve for n
0.0001*sqrt(n) = 0.00196
sqrt(n) = 19.6
n = 4.427188724
Since you can't have a fractional value for n, then n should be at least 5 for a 95% confidence interval that the measured mean is within 0.0001 grams of the correct mass.</span>
Answer:
8.4
Step-by-step explanation:
(7/8) (4) = 3.5
(1/10) (8) = 0.8
3.5 × 0.8 × 3 = 8.4
Hope this helps.
Polynomials in the fourth degree are called quartic equations. In solving the roots of polynomials, there are techniques available. For quadratic equations, you use the quadratic formula. For cubic equations, you use the scientific calculator. But for quartic equations and higher, it is very complex. The method is very lengthy and can get very messy because you introduce a lot variables. So, I suggest you do the easiest method to estimate the roots.
Graph the equation by plotting arbitrary points. The graph looks like that in the figure. The points at which the curve passes the x-axis are the solution which are encircled in red.In approximation, the rational roots or zero's are
-3.73, -1, -0.28 and 2.
