Answer:
And rounded up we have that n=385
Step-by-step explanation:
Previous concepts
A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".
The margin of error is the range of values below and above the sample statistic in a confidence interval.
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
Solution to the problem
In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 99% of confidence, our significance level would be given by
and
. And the critical value would be given by:
The margin of error for the proportion interval is given by this formula:
(a)
And on this case we have that
and we are interested in order to find the value of n, if we solve n from equation (a) we got:
(b)
We can use as an estimator for p
. And replacing into equation (b) the values from part a we got:
And rounded up we have that n=385
Answer: 3
Step-by-step explanation:
Multiply 7 x 5.2
Divide 109.2/36.4
Answer 3
So, we know the slope equation y = mx + b. The b value represents the y intercept, which is the point where the line intersects the y axis. This means that the x value will always be 0. In this equation, the y-intercept is -2, so the y intercept as an ordered pair is : (0, -2). For the x intercept, there are several ways of doing it. For this problem, we can work backwards. There is a slope of 6 units down for every unit right. Starting from our y intercept, we can do the opposite: 6 units up for every unit left. this means our x intercept is -0.3. As an ordered pair, this is (-0.3, 0).
Answer:
Step-by-step explanation:
Let width be x m
perimeter = 2L + 2W
W = x and L = 4W - 7 = 4x - 7
so we have the equation
2(4x - 7) + 2x = 136
8x - 14 + 2x = 136
10x = 150
x = 15
So the width = 15m and the length = 4(15) -7 = 53 m. Answer