Hi, I am so confused on how to do this problem.
An executive in an Austrailian savings bank decides to estimate the mean amount of money withdrawn in bank machine transactions. From past experiences, she belives that $50 (Austrailian) is a reasonable guess for the standard deviation of the distribution of withdrawls. She would like her sample mean to be within $10 of the population mean. Estimate the probability that this happens if she randomly samples 100 withdrawls. (Hint: Find the standard error of the sample mean. How many standard errors does $10 equal?)
It sounds like it has to be derived from a formula and manipulated algebrically to set it up to equal $10. Can somebody show me how to set this up?
The only formula I could find to maybe start with was SE = standard deviation/sq. n. For here I thought it was SE = 50/10 = 5. Am I on the right track?
An executive in an Austrailian savings bank decides to estimate the mean amount of money withdrawn in bank machine transactions. From past experiences, she belives that $50 (Austrailian) is a reasonable guess for the standard deviation of the distribution of withdrawls. She would like her sample mean to be within $10 of the population mean. Estimate the probability that this happens if she randomly samples 100 withdrawls. (Hint: Find the standard error of the sample mean. How many standard errors does $10 equal?)
It sounds like it has to be derived from a formula and manipulated algebrically to set it up to equal $10. Can somebody show me how to set this up?
The only formula I could find to maybe start with was SE = standard deviation/sq. n. For here I thought it was SE = 50/10 = 5. Am I on the right track?