Tim's phone service charges $24.39 plus an additional $0.24 for each text message sent per month. If Tim's phone bill was $30.39
1 answer:
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Answer:
c. 6.2 ± 2.626(0.21)
Step-by-step explanation:
We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 101 - 1 = 100
99% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 100 degrees of freedom(y-axis) and a confidence level of . So we have T = 2.626
The confidence interval is:
In which is the sample mean while M is the margin of error.
The distribution of the number of puppies born per litter was skewed left with a mean of 6.2 puppies born per litter.
This means that
The margin of error is:
In which s is the standard deviation of the sample and n is the size of the sample.
Thus, the confidence interval is:
And the correct answer is given by option c.