Answer: 37
Step-by-step explanation:
Given : Significance level : 
Critical value : 
margin of error : E= 1 mile per gallon
Population standard deviation:
miles per gallon.
We know that when the population standard deviation is known then the formula to find the sample size is given by :

[Round to the next whole number.]
Hence, the required number of automobiles should be used in the test = 37
Answer:
all work is shown and pictured
Answer:
x = 3
Step-by-step explanation:
4 + 12.5 > 11x - 3.5 - 2x
16.5 = 5.5x
16.5/5.5 = x
Cramer's Rule is a method that uses determinants to solve systems of equations that have the same number of equations as variables