3. ed and adelaide attend the same high school,
laide attend the same high school, but are in different math classes. the time e that
es ed to do his math homework follows a normal distribution with mean 25 minutes and
iard deviation 5 minutes. adelaide's math homework time a follows a normal distribution
with mean 50 minutes and standard deviation 10 minutes. assume that e and a are
independent random variables.
a.) randomly select one math assignment of ed's and one math assignment of adelaide's. let
the random variable d be the difference in the amount of time each student spent on their
assignments: d = a - e. find the mean and standard deviation of d. show your work.

7

step-by-step explanation:

introduction, methodology, results, discussion

step-by-step explanation:

an observational study is one which consists of actual observation to record data and then analyse the data.

there are a number of factors that should be analyzed before starting an observational study.

the main four factors are:

i) introduction:   this should be analysed to check whether the purpose of the study is correctly established and the data recorded are appropriate for the study

methodology:   the method of collecting the data, such as whether randomly selected, and whether sample size matches with the population to be studied, whether questions asked are easy to answer by common men, etc.

results: then results such as summary of data with comments should be studied thoroughly

discussion:   the last is the discussion, this can be either by management people or persons who are all interested , etc.