Identify the sequence as arithmetic, geometric, or neither 3, 4.5,6,7.5

In an arithmetic sequence we have a common difference (d).

Common difference: The common difference is the difference between two numbers in an arithmetic sequence.

So let us find common difference for the given sequence:

3, 4.5,6,7.5

Here first term is 3,

second term is 4.5

Difference = second term - first term = 4.5 - 3 = 1.5

third term is 6,

Difference = third term - second term = 6- 4.5 = 1.5

So common difference is 1.5

So we can say that the given sequence is an arithmetic sequence.

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.