Solved on Dec 05, 2023
Find the margin of error for , , and .
STEP 1
Assumptions
1. The confidence level () is 0.95.
2. The sample standard deviation () is 4.
3. The sample size () is 8.
4. The margin of error is calculated using the formula for a t-distribution, as the population standard deviation is unknown and the sample size is small ().
5. The margin of error formula for a t-distribution is given by:
where is the t-score that corresponds to the confidence level and degrees of freedom (), is the sample standard deviation, and is the sample size.
STEP 2
Determine the degrees of freedom for the t-distribution.
STEP 3
Plug in the value of to find the degrees of freedom.
STEP 4
Determine the value of (alpha), which is the probability in the tails (the complement of the confidence level).
STEP 5
Plug in the value of to find .
STEP 6
Since the t-distribution is symmetric, the probability in each tail is .
STEP 7
Find the t-score () that corresponds to the given confidence level and degrees of freedom. This is typically done using a t-distribution table or a calculator with statistical functions.
STEP 8
For a confidence level of 0.95 and 7 degrees of freedom, the t-score is approximately 2.365 (this value may vary slightly depending on the t-distribution table or calculator used).
STEP 9
Now that we have the t-score, we can calculate the margin of error using the formula.
STEP 10
Plug in the values for , , and to calculate the margin of error.
STEP 11
Calculate the square root of .
STEP 12
Now, divide the sample standard deviation by the square root of the sample size.
STEP 13
Multiply the t-score by the result from the previous step to find the margin of error.
STEP 14
Calculate the margin of error.
The margin of error for the given values of , , and is approximately 3.344.
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