Thread: statistic

the average lenght of a hospital stay is 5.9 days if we assume a normal distribution and a standard deviation of 1.7 days 15% of hospital stays are less than how many days? 25% of hospital stays are longer than how many days?

These are z-score lookup problems.

What z-score keeps 15% in the left tail? I'll call it 'a'.

Then (Days-5.9)/1.7 = a. Solve for 'Days'.