Answer:
And rounded up we have that n=2663
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".
The population proportion have the following distribution
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 assume an estimated proportion of
since we don't have prior info provided. And replacing into equation (b) the values from part a we got:
And rounded up we have that n=2663
Answer:
33.33 gallons
Step-by-step explanation:
1000 miles divided by 30 miles per gallon.
Answer:
16ft
Step-by-step explanation:
use pythagreom thereom
12^2+b^2=20^2 solve
144+b^2=400
b^2= 256 square it
b= 16
To answer this question you will set up the proportion shown in the attached picture.
There are 2 ways to solve this.
1. You can create an equivalent ratio by determining the factor that will take you from 1 cm to 2 cm and apply his factor to the 19 miles.
The answer would be 19 x 2= 38 miles for 2 centimeters.
2. The second strategy is to use cross products to get an answer. You multiply the number diagonal from each other. See picture for this work.
Answer: C
Step-by-step explanation: