Forty of the staff of 85 teachers at a local intermediate school are certified in Cardio-Pulmonary Resuscitation (CPR). In 180 days of school, what would be the expected mean, variance and standard deviation?

Answer and Step-by-step explanation:

The computation is shown below;

Here we use the binomial distribution

p = 40 ÷ 85 = 0.47

q = 1 -0.47 = 0.53

n = 180

Now  

mean

= np

= 180 × 0.47

= 84.6

The Variance is

= npq

= 180 ×  0.47 × 0.53

= 44.84

And,  Standard deviation

= √npq

= √44.84

= 6.69

We simply applied the above formula so that the correct value could come

And, the same is to be considered  

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.

no he doesnt because "-16' is negatiive

step-by-step explanation: