Answer:
31.92%
Step-by-step explanation:
We are given;
Population mean; μ = $3.12
Sample mean; x¯ = $3.16
Sample size; n = 10
Standard deviation; σ = $0.27
Z-score formula is; z = (x¯ - μ)/(σ/√n)
z = (3.16 - 3.12)/(0.27/√10)
z = 0.04/(0.08538)
z ≈ 0.47
Now, the percent of other sample means, based on 10 gas stations, that would be greater than the one observed is;
P(x¯ > 3.12) = 1 - P(z < 0.47)
From z-table attached P(z < 0.47) = 0.68082
Thus;
P(z > 0.47) = 1 - 0.68082
P(z > 0.47) ≈ 0.3192
This expressed in percentage is 31.92%
 
        
             
        
        
        
Answer:
$28.12
Step-by-step explanation:
$9.19 x 40 = $367.60 x 7.65% = $28.12
 
        
             
        
        
        
Answer:
one solution
x = 12
Step-by-step explanation:
3 (x-1) = 2x + 9
3x - 3 = 2x + 9
subtract 2x from each side of the equation:
x - 3 = 9
add 3 to each side:
x = 12
 
        
                    
             
        
        
        
X^2-14+5 I’m not sure though