Help me its math khan academy 8th grade math

95%

Step-by-step explanation:

So, we can see on the chart that 78 out of 82 people from ages 18 to 22 use Face.book. So we're trying to find what percentage 78 is of 82:

The first step is to write 78 as a fraction of 82, which is:

78/82

In order to find the simplest form of 78/82 we cancel out the greatest common divisor of 78 and 82, which is 2 :

78/82 = 37/41  

Now we just need to convert this fraction to a percentage :

 37/41 = 95% (rounded)

So we have the final answer :

78 is 95% of 82

Which means that:

Approximately 95% of people from ages 18 to 22 use Face.book

hope this helps:)

35%

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.