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The average gas mileage (mpg) for vehicles produced by a particular automotive company is 26 mpg, with a standard deviation of 2 mpg. What percentage of the vehicles produced by the automotive company have a gas mileage greater than 24?

Note: Assume that a Normal model is appropriate for the distribution of the gas mileages for the vehicles.

About 68% of the vehicles have a gas mileage greater than 24 mpg.

About 32% of the vehicles have a gas mileage greater than 24 mpg.

About 84% of the vehicles have a gas mileage greater than 24 mpg.

About 16% of the vehicles have a gas mileage greater than 24 mpg.​

User Vny Kumar
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Final answer:

Using the normal distribution, a Z-score calculation for 24 mpg results in finding that approximately 84% of the vehicles have a gas mileage greater than 24 mpg.

Step-by-step explanation:

To determine the percentage of vehicles that have a gas mileage greater than 24 mpg, we can use the properties of the normal distribution. Given the average (mean) gas mileage is 26 mpg with a standard deviation of 2 mpg, we can calculate the Z-score for a gas mileage of 24 mpg.

The Z-score is given by the formula:

Z = (X - μ) / σ

Where X is the value we are interested in (24 mpg), μ is the mean (26 mpg), and σ is the standard deviation (2 mpg).

Z = (24 - 26) / 2 = -2 / 2 = -1

A Z-score of -1 corresponds to a percentile rank of approximately 15.87% on the lower end, meaning 15.87% of vehicles have a gas mileage less than 24 mpg. To find the percentage greater than 24 mpg, we subtract this from 100%.

100% - 15.87% = 84.13%

Therefore, approximately 84% of the vehicles produced by the company have a gas mileage greater than 24 mpg.

User George Saad
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