A random sample of 100 undergraduate students at a university found that 78 of them had used the university library’s website to
find resources for a class. What is the margin of error for the true proportion of all undergraduates who had used the library’s website to find resources for a class?
It depends upon the confidence level (99%, 95%, etc) of the sample. In this case, the population size is 100, and the sample size is 78. If it's in a 99% confidence level, margin of error is 7 (So between 71 - 85 undergrads). If it's in a 95% confidence level, the margin of error is 6 (So between 72 - 84 undergrads).
if either or both of and are 0, i.e. if one or both of and are even. But both will be even if is even, and odd otherwise, so any even will be a solution, e.g. .