Answer:
A sample size of 1031 is required.
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 of:
37% of freshmen do not visit their counselors regularly.
This means that
98% confidence level
So , z is the value of Z that has a pvalue of , so .
You would like to be 98% confident that your estimate is within 3.5% of the true population proportion. How large of a sample size is required?
A sample size of n is required.
n is found when M = 0.035. So
Rounding up:
A sample size of 1031 is required.
Answer:
-2
Step-by-step explanation:
I hope that it's a clear solution.
Answer:
4
Step-by-step explanation:
Given
2x + 5 < 1 ( subtract 5 from both sides )
2x < - 4 ( divide both sides by 2 )
x < - 2
Since x is less than - 2, it cannot equal - 2 but can be equal to the other values given in the list
For word problems, assign variables so you can express them into equations. For this problem, the unknown is the number of each animals. Let's assign x to the number of cows and y to the number of chickens. It is mentioned that there are a total of 28 animals. Therefore, we can formulate the first independent equation to be
x + y = 28 ---> eqn 1
Next, we know that the total number of legs are 74. Since each cow has 4 legs and each chicken has 2 legs, the second independent equation we could formulate is:
4x + 2y = 74 ---> eqn 2
Now, we have a system of linear equations. There are two unknowns and two independent equations. Thus, the system is solvable. Let's use the method of substituting to solve this. Rearrange eqn 1 such that x is a function of y. Let's denote this as eqn 1'.
x = 28 - y ---> eqn 1'
Substitute eqn 1' to eqn 2:
4(28 - y) + 2y = 74
112 - 4y + 2y = 74
-2y = 74 - 112
-2y = -38
y = -38/-2
y = 19
Therefore, there are 19 chickens. Now, we use y=19 to substitute to eqn 1:
x + 19 = 28
x = 28 - 19
x = 9
Therefore, there are 9 cows.