We are doing a study on shampoo buyers in Walmart stores across the US and we send them online surveys. Based on past studies, w
e know that of the people who start the survey, 80% qualify for the study, and only 40% of these people who do qualify actually complete the survey. Of the people who complete the survey, 10% of respondents are removed due to invalid or low quality answers. If we want 1000 valid responses for this particular study, how many people do we need to have start the survey?
Probability is typically the rate at which an event or occurrence is likely to happen. Whenever we're not so sure about an event outcome, we can then deliberate about the probabilities or possibility of certain outcomes that is how likely they are to happen.
Starting from what I know (the difference between ribbons), I decided to go from the bottom and work my way up. I then noticed a pattern (each sum was three more of the previous one), and decided to keep my pattern of the three numbers but not have to do any major mental work and instead add three to the previous sum until I got to 38.
