The athletic club at school sold raffle tickets to raise money for equipment. The club sold a total of 1050 tickets,515 to teachers and 235 tickets to staff. If the winning ticket was picked at random what is the probability of the teacher or other staff member?

Probability of the teacher or other staff is 0.7143

Step-by-step explanation:

pr(teacher or other staff) = pr(teacher) + pr(other staff) - pr(teacher and other staff)

Total number of tickets = 1050

Number of tickets sold to teachers = 515

Number of tickets sold to other staff = 235

pr(teacher) =

                 = 103

                 = 0.4905

pr(other staff) =

                    = 47

                  = 0.2238

Since the picking of the wining ticket is mutually exclusive, then;

pr(teacher and other staff) = 0

Thus,

pr(teacher or other staff) = 0.4905 + 0.2238 - 0

                                         = 0.7143

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.