how many adults must be randomly selected to estimate the mean FICO score of working adults in the United States. We want 95% confidence that the sample mean is within 3 points of the population mean, and the population standard deviation is 68

Question

anonymous · Answer

What formula do you know?

Is this something like Chebyshev?

kropot72 · Answer

Substitute the given values into the following formula and solve for n (the sample size).
$$\bar {x}-1.96\frac{\sigma}{\sqrt{n}}<\mu < \bar {x}+1.96\frac{\sigma}{\sqrt{n}}$$