Answer:
a. 19.68 miles per gallon.
b. 26.32 miles per gallon.
Step-by-step explanation:
Mean gas mileage (μ) = 23.0 mpg
Standard deviation (σ) = 4.9 mpg
In a normal distribution, for any length X, the z-score is determined by the following expression:
In a normal distribution, the 25th percentile (first quartile) of a normal distribution has a corresponding z-score of z = -0.677 and the 75th percentile has a corresponding z-score of z = 0.677
a. The first quartile of the distribution of gas mileage is
19.68 miles per gallon.
b. The third quartile of the distribution of gas mileage is
26.32 miles per gallon.