The mean gas mileage for a hybrid car is 56 miles per gallon. Suppose that the gasoline mileage is approximately normally distributed with a standard deviation of 3.2 miles per gallon. (a) What proportion of hybrids gets over 61 miles per gallon? (b) What proportion of hybrids gets 50 miles per gallon or less? (c) What proportion of hybrids gets between 58 and 62 miles per gallon? (d) What is the probability that a randomly selected hybrid gets less than 46 miles per gallon? Click the icon to view a table of areas under the normal curve. (a) The proportion of hybrids that gets over 61 miles per gallon is (Round to four decimal places as needed.)

Suppose a professor uses a normal distribution to assign grades in her math class. • She assigns an A to students scoring more than 1.9 standard deviations above the mean. • She assigns an F to students scoring more than 2.2 standard deviations below the mean. She assigns a B to students who Score between 1 and 1.9 standard deviations above the mean. • She assigns a D to students who Score between 1.2 and 2.2 standard deviations below the mean. • All other students get a C. Use the Cumulative Z-Score Table to answer the following questions. The Z-Score Table can be found below by selecting "Read". Write your answer as a percent using 2 decimal places. What percent of the class receives each grade assuming the scores are normally distributed? Hint % will recieve an A % will recieve a B % will recieve a C % will recieve a D % will recieve an F

The annual income for a sample of 450 part-time students is normally distributed with a mean income of $31,000 and a standard deviation of $3,000.   What is the probability their annual income is more than $35,000?

Seventy million pounds of trout are grown in the U.S. every year. Farm-raised trout contain an average (mean) of 32 grams of fat per pound, with a standard deviation of 8 grams of fat per pound. A random sample of 40 farm-raised trout is selected. The mean fat content for the sample is 30.2 grams per pound. Find the probability of observing a sample mean of 30.2 grams of fat per pound or less in a random sample of 40 farm-raised trout. Carry your intermediate computations to at least four decimal places. Round your answer to at least three decimal places. Check esc 23 2$ 5 2 e r t y tab