Could Someone Please Help Me Answer This Statistics Problem?

Question

Consider the following example: Data on social media use was collected from a sample of college students. The average daily amount of social media use by this group was found to be 3.4 hours, with a standard deviation of 1.2 hours. Consider your daily social media use, and then develop a main response in which you address the following:

1. Identify and state approximately how many hours you used social media today. ( I use 2 hours a day)
2. Use the sample mean (3.4 hours) and standard deviation (1.2 hours) provided to calculate a z-score for your own daily social media use.
3. Use the normal distribution table in your textbook or technology (like NORMALCDF on a TI 83/84) to determine the percentile for your z-score.
4. Explain what this means, and what it implies about your social media use in comparison to the sample. 

Answer 1

Hi Taylor,

Question 2.

This question uses the classic equation in elementary statistics:

z= (x-mu)/sigma

Now, based on the data we were given, and the question specifically asking for a z-score, we have to assume the data are approximately normally distributed and the values you were given for mu and sigma were indeed from a population. If it were truly from a sample, we would need to know sample size and compute an additional statistic called standard error. Anyway:

x=2 hours, your social media usage

mu=3.4

sigma=1.2

z= (2-3.4)/1.2

z= -1.17

Question 3

Look up a z-table online; I cannot link here as Wyzant reviews posts with links. Look for -1.1 in the column, 0.07 in the row.

P(Z<2) = 0.1210, about the 12th percentile

Question 4

This means that your social media use is far below average, based on the data you were given.

I hope this helps.