Question

Lexus has a mean gas gallon per mile of .3 and standard deviation of .025. Chevrolet has a mean gas gallon per mile of .37 and standard deviation of .022. Your Lexus consumes .32 gas gallon per mile and your Chevrolet consumes .35 gas gallon per mile. Which one of your two cars consumes more gas compared to their own brands

Answer 1

Solution :

Given that ,

mean = = 0.3 ( Lexus )

standard deviation =  = 0.025

x = 0.32

Using z-score formula,

z = x - /   

z = 0.32 - 0.3 / 0.025

z = 0.80 ( Lexus )

mean = = 0.37 ( Chevrolet )

standard deviation =  = 0.022

x = 0.35

Using z-score formula,

z = x - /   

z = 0.35 - 0.37 / 0.022

z = -0.91 ( Chevrolet )

Lexus cars consumes more gas compared to their own brands