Chapter 7 4) According to a report by the U.S. Fish and Wildlife Service, the mean length of s rainbow trout in the Arolik River in Alaska is 479 millimeters with a standard deviation of 41 millimeters. Assume these lengths are normally distributed. (a) What proportion of six-year-old rainbow trout are less than 451 millimeters long? (b) What proportion of six-year-old rainbow trout are between 420 and 518 millimeters long? (c) Is it unusual for a six-year-old rainbow trout to be less than 412 millimeters long?

The shelf life of a batteries produced by one major company are normally distributed with a mean of 4.3 years and a standard deviation of 0.6 years. The figure below shows the distribution of shelf lives of batteries produced by one major company. Calculate the shaded area under the curve. Answer:

John Beale of Stanford, California, recorded the speeds of cars driving past his house, where the speed limit read 20 mph. The mean of 100 representative readings was 23.76 mph, with a standard deviation of 3.53 mph. a) How many standard deviations from the mean would a car going the speed limit be? b) Which would be more unusual, a car traveling 35 mph or one going 8 mph? a) A car traveling at the speed limit is from the mean. (Round to two decimal places as needed.) b) Choose the correct answer below and fill in the answer box(es) to complete your choice. (Round to two decimal places as needed.) OA. B. standard deviations O C. The car traveling 35 mph is more unusual. It is standard deviations from the mean, while the car traveling 8 mph is standard deviations from the mean. The car traveling 8 mph is more unusual. It is standard deviations from the mean, while the car traveling 35 mph is standard deviations from the mean. Both cars are equally unusual. Both cars are standard…

In​ 2011, the mean property crime rate​ (per 100,000​ people) for 10 northeastern regions of a certain country was 2367. The standard deviation was 394. Assume the distribution of crime rates is unimodal and symmetric. What percentage of northeastern regions would you expect to have property crime rates between 1973 and 2761.

a) In the process of designing an airplane, men were measured to determine the size of the seat that was needed. Men have mean hip width of 36.6 cm and a standard deviation of 2.5 cm. Copy and complete the picture below as we have done in class. b) What percentage of men will have hip widths between 36.6cm and 44.1 cm c) About 95% of men will have hip widths between what lengths?