I. Introduction:
a. My group and I designed a survey to find out if our friends and acquaintances exercised, and whether or not they were concerned about their exercise habits. This was not a random survey, as we used Facebook, email and face to face contacts to get our results. This was a voluntary survey, and not everyone asked responded.
b. We asked the following questions:
 Do you currently exercise? Yes or No
 How old are you? ____ years
 How many hours of exercise a week do you think an average person requires to be healthy? _____hours
 How concerned are you with your level of activity? Select one: Highly concerned, Moderately concerned, Not at all concerned?
II. Looking at a Categorical Variable
a. The responses to the question " Do you currently exercise?" are shown in the pie chart below.
Result 1: Pie Chart Responses to Currently Exercise?
From the pie chart above we can see that 54 of the 100 people we polled (54%) said that they do currently exercise. Fortysix (46%) do not currently exercise.
b.
Result 2: A sample proportion with summary
95% confidence interval results:
p: proportion of successes for population
Method: StandardWald
One sample proportion confidence interval:Outcomes in : Exercise? Success : Yes p : Proportion of successes Method: StandardWald 95% confidence interval results:

Interpretation of the confidence interval: Above is the 95% confidence interval results for the proportion of the population that would answer "yes" to the question "Do you currently exercise?". A 95% confidence interval means that if you select multipe different samples of size n=100, approximately 95% would result in confidence intervals that contain the true proportion p. The above results can be interpreted as saing we are 95% confident that our confidence interval contains the true proportion, and we are 95% confident the true proportion of our population would answer yes to this question is between 0.442 to 0.638.
The error term E=(.638.054)/2=0.083/2= 0.042 (margin of error).
III. Looking at a Numerical Variable
a.
The responses to the question "How many hours of exercise a week do you think an average person requires to be healthy?" are shown in the histogram and summary statistics below.
Result 3:
Result 4: Summary Statistics for Hours per Week Required
Summary statistics:

b.
A 95% confidence interval for the population mean is shown below.
One sample T confidence interval:μ : Mean of variable 95% confidence interval results:

Interpretation of the confidence interval: a 95% confidence interval means that if we selected many diffferent sample s of size n=100, approximately 95% of these would result in confidence ntervals that contain the true proportion mean u. We can interpret the above reults by saying we are 95% confident that our confidence interval contains the true proportion mean. So, we are 95% confident that within our population, the average person thinks we need between 5.5 and 7.4 hours per week.
The tdistribution was used becasue the sample size is more than 30 and the population standard deviation is not known.
Interpretation of the confidence interval:
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