4. Which proportion of a normal distribution is located between the mean and z = +1.40? 5. A vertical line drawn through a normal distribution at z = +2.11 separates the distribution into two sections, the body and the tail. Which proportion of the distribution is in the tail?

Use the standard normal distribution to compare two other normal distributions. 25. Blood pressure is described by two numbers: systolic pressure and diastolic pressure (measured in mmHg, or millimeters of mercury). For example, a blood pressure of 120/80 denotes a systolic pressure of 120 mmHg and a diastolic pressure of 80 mmHg. A study of 625 persons ages 26 to 45 finds that their blood pressures are normally distributed. Their systolic pressure had a mean of 122 and a standard deviation of 14, and their diastolic pressure had a mean of 83 and a standard deviation of 9. Two study participants are randomly selected and their blood pressures are measured again. The first participant had a systolic reading of 99 mmHg, while the second had a diastolic reading of 70 mmHg. Which participant had the lower reading with regard to the study population? 26. Health experts often consider blood pressure to be elevated if systolic pressure is 140 or greater or the diastolic pressure is 90 or…

Determine whether the graph shown could represent a variable with a normal distribution. Explain your reasoning. If the graph appears to represent a normal distribution, estimate the mean and standard deviation. 32 35 38 41 44 47 50 53 56 E. The graph could represent a variable with a normal distribution because the curve is symmetric and bell-shaped. Its mean is approximately 44, and its standard deviation is approximately 32. (Round to one decimal place as needed.) Q right. O C. The graph could not represent a variable with a normal distribution because the curve has two modes. O D. The graph could not represent a variable with a normal distribution because the curve crosses the x-axis. O F. The graph could not represent a variable with a normal distribution because the graph is skewed to the left. 4

The annual per capita consumption of ice cream (in pounds) in the United States can be approximated by the normal distribution, as shown in the figure to right. the (a) What is the largest annual per capita consumption of ice cream that can be in the bottom 9% of consumptions? (b) Between what two values does the middle 80% of the consumptions lie? UN H=19.8 4.3 8 20 32 Consumption (in lbs)