The average playing time of music albums in a large collection is 36 minutes, and the standard deviation is 3 minutes. (a) What value is 1 standard deviation above the mean? 1 standard deviation below the mean? What values are 2 standard deviations away from the mean? 1 standard deviation above the mean 1 standard deviation below the mean 2 standard deviations above the mean 2 standard deviations below the mean (b) without assuming anything about the distribution of times, at least what percentage of the times are between 30 and 42 minutes? (Round the answer to the nearest whole number.) At least % (c) without assuming anything about the distribution of times, what can be said about the percentage of times that are either less than 27 minutes or greater than 45 minutes? (Round the answer to the nearest whole number.) No more than %

Arsenic is a compound that occurs naturally in very low concentrations. Arsenic blood concentrations in healthy adults are Normally distributed, with mean ?=3.2 micrograms per deciliter (?g/dl) and standard deviation ?=1.5 μg/dl . What is the range of arsenic blood concentrations corresponding to the middle 90% of healthy adults? Use Table B or technology to find the proper values

The length of human pregnancies from conception to birth varies according to a distribution that is approximately Normal with mean 269 days and standard deviation 19 days.Use a normal z-table to answer all questions below. If not,your answers may be marked as incorrect due to rounding issues.(a) What proportion of pregnancies last less than 270 days (about 9 months)? (Use 4 decimal places)(b) What proportion of pregnancies last between 240 and 270 days (roughly between 8 months and 9 months)? (Use 4 decimal places)(c) The longest 20% of pregnancies last  days or longer. (Round to an integer.)(d) What are the quartiles of the distribution of lengths of human pregnancies? Q1 =  days (Round to an integer.)Q3 =  days (Round to an integer.)

The lengths of pregnancies in a small rural village are normally distributed with a mean of 265 days and a standard deviation of 16 days. In what range would you expect to find the middle 95% of most pregnancies? Between and If you were to draw samples of size 59 from this population, in what range would you expect to find the middle 95% of most averages for the lengths of pregnancies in the sample? Between and Enter your answers as numbers. Your answers should be accurate to 1 decimal places. Question Help: Message instructor Submit Question 824 tv esc 20 888 F1 F2 F3 F4 F5 F6 @ # $ % & 1 2 4 Q W Y T