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Seng, Christopher, Lab 8
Generated Apr 16, 2019 by christopher723469

1. What type of variable is "number of drinks?"

The type of variable is quantitative and discrete.

2. Create a histogram of the data and comment on the shape of the distribution.

The distribution is skewed right for this data.

3. Calculate the mean and standard deviation for the number od drinks, and determine the mode.

Mean:2.0494. Standard Deviation: 1.5500. Mode: 1

4. What is the probability that a randomly selected individual consumes two drinks?

P(2 drinks)= 66/243 = approx .2716%

5. Would it be unusual to observe a randomly selected individual who consumes at least eight drinks? why?


P(x at least 8)= 2/243 = approx .0082. It would be unusual to observe a randomly selected individual who consumes at least eight drinks due to .0082% being under 5%.

6. Describe the shape of the sampling distribution of the mean number od drinks if groups of 35 randomly selected individuals are asked about their drinking habits. What is the source of variability in the sampling distribution?

P-hat= 35/243 = approx. .1440. (243)(.1440)(1-.1440)= 29.9532 which is greater than or equal to 10. The shape of the sampling distribution of the mean number of drinks is there are 35 randomly selected individuals is approximately normal. The source of variability is the individuals surveyed.

7. Construct and interpret a 95% confidence interval for the mean number of drinks.


We are 95%  confident that the mean number of drinks is between 0.9989 and .18818

Result 1: Lab8Histogram   [Info]
Right click to copy



Result 2: Lab8Stats   [Info]

Summary statistics:


ColumnMeanStd. dev.Mode
Drinks2.04938271.55000321



Result 3: Lab8CI   [Info]

One sample T confidence interval:


μ : Mean of variable

95% confidence interval results:
VariableSample MeanStd. Err.DFL. LimitU. Limit
Drinks2.04938270.0994327522421.85351862.2452469