Answer:
The 90% confidence interval for the population standard deviation waiting time for an oil change is (3.9, 6.3).
Step-by-step explanation:
The (1 - <em>α</em>)% confidence interval for the population standard deviation is:

The information provided is:
<em>n</em> = 26
<em>s</em> = 4.8 minutes
Confidence level = 90%
Compute the critical values of Chi-square as follows:


*Use a Chi-square table.
Compute the 90% confidence interval for the population standard deviation waiting time for an oil change as follows:


Thus, the 90% confidence interval for the population standard deviation waiting time for an oil change is (3.9, 6.3).
Answer:
34
Step-by-step explanation:
you just have to subtract 13 from 47
Answer:
x= -1, -13
Step-by-step explanation:
Answer:
2x^3-6x^2-14x+24
Step-by-step explanation:
Answer:
Standard error = 0.4
Step-by-step explanation:
Step 1
We find the Standard Deviation
The formula = √(x - mean)/n - 1
n = 15
Mean = 1.93 hours
= √(0- 1.93)² + (0-1.93)² +(0- 1.93)²+( 0- 1.93)²+ (1- 1.93)² + (1- 1.93)² +(1 - 1.93)² +(2 - 1.93)² + (2 - 1.93)² + (2 - 1.93)² + (2 - 1.93)² + ( 2 - 1.93)² +(4 - 1.93)² +(4 - 1.93)² + (5 - 1.93)²/15 - 1
= √(3.737777776 + 3.737777776 + 3.737777776 + 0.871111111 +0.871111111 + 0.871111111 + 0.004444444445+ 0.004444444445 + 0.004444444445 + 0.004444444445 + 0.004444444445 + 1.137777778 + 4.271111112 + 4.271111112 + 9.404444446)/15 - 1
= √2.352380952
= 1.533747356
Step 2
We find the standard error
The formula = Standard Deviation/√n
Standard deviation = 1.533747356
n = 15
= 1.533747356/√15
= 1.533747356 /3.87298334621
= 0.39601186447
Approximately = 0.4
Therefore, the standard error is 0.4