Reference no: EM132377053

1. Fuel economy estimates for automobiles built one year predicted a mean of 27.8 mpg and a standard deviation of 5.2 mpg for highway driving. Assume that a Normal model can be applied. Use the 68-95-99.7 Rule.

a. In what interval would you expect the central 68?% of autos to be? found? Using the? 68-95-99.7 rule, the central 68?% of autos can be expected to be found in the interval from ____ to _____ mpg.

2. In one season of a football? league, the number of yards gained by each of the 168 wide receivers was recorded. The mean is 473 ?yards, with a standard deviation of 341 yards.

a. ?According to the Normal? model, what percent of receivers would you expect to gain fewer yards than 2 standard deviations below the mean number of? yards? Use the 68-95-99.7 rule.

3. Companies who design furniture for elementary school classrooms produce a variety of sizes for kids of different ages. Suppose the heights of kindergarten children can be described by a Normal model with a mean of 39.2 inches and standard deviation of 1.9inches.

a. What fraction of kindergarten kids should the company expect to be less than 33 inches? tall?