Frankie washed 15 cars in three hours.
How many cars can
he wash in seven
hours?

It’s either 35 or 41.

35

This means he took 60 mins/5 to wash each car = 12 mins.

7 hours = 7* 60 mins= 420 mins

cars he washed in 7 hours = 420/12 = 35

OR

he took 3 hours to wash 15 cars so he can wash 30 in 6 hours, hs rate = 5 cars/ hour = 30 + 5 = 35

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.