The average fuel consumption for passenger vehicles is 28 miles per gallon with a standard deviation of 4 miles per gallon. Assume gas mileage is approximately bell-shaped. (a) 99.7% of cars will have gas mileage between what two values? (b) What is the maximum gas mileage a car could have to be in the bottom 2.5% of cars? (c) What percent of cars have gas mileage between 24 and 40 miles per gallon? (d) What gas mileage does a car require to be considered an outlier?
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7% of the data falls within 3 standard deviations of the mean. Mean = 28 miles per gallon Standard deviation = 4 miles per gallon Lower bound: $28 - 3(4) = 28 - 12 = 16$ Upper bound: $28 + 3(4) = 28 + 12 = 40$ So, 99.7% of cars will have gas mileage between 16 and Show more…
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