The physical plant at the main campus of a large state university recieves daily requests to replace florecent lightbulbs. The distribution of the number of daily requests is bell-shaped and has a mean of 42 and a standard deviation of 10. Using the 68-95-99.7 rule, what is the approximate percentage of lightbulb replacement requests numbering between 42 and 72? Do not enter the percent symbol. ans = %

There are eight patients waiting in a doctor's waiting room.  They have been waiting for 9 minutes, 2 minutes, 5 minutes, 4 minutes, 12 minutes, 7 minutes, 8 minutes, and 11 minutes.  Calculate the population standard deviation for the patients' wait times (in minutes). Round to the nearest hundredth as needed.

Assume that the readings at freezing on a batch of thermometers are normally distributed with a mean of 0°C and a standard deviation of 1.00°C. A single thermometer is randomly selected and tested. Find P., the 58- percentile. This is the temperature reading separating the bottom 58% from the top 42%. P = °C Question Help: D Post to forum Submit Question Type here to search 耳

A company produces steel rods. The lengths of the steel rods are normally distributed with a mean of 241.2-cm and a standard deviation of 0.6-cm.Find P22, which is the length separating the shortest 22% rods from the longest 78%.P22 =