Answer:
critical value = 1.645
The 90% confidence interval = ( -22.62, -17.58)
Step-by-step explanation:
Given that:
the sample size
= 178
the sample size
= 226
the sample mean
= 54.4
the sample mean
= 74.5
population standard deviation
= 18.58
population standard deviation
= 9.52
level of significance ∝ = 1 - 0.90 = 0.10
The critical value for
is 1.645
For the construction of our confidence interval, we use 90% since that is used to find the critical value.
∴
The margin of error = 



2.52
The lower limit = 
= ( 54.4-74.5) - (2.52)
= -20.1 - 2.52
= -22.62
The upper limit = 
= ( 54.4-74.5) + (2.52)
= -20.1 + 2.52
= -17.58
The 90% confidence interval = ( -22.62, -17.58)
Answer:
Your question is incomplete pleasegove the real question.
Step-by-step explanation:
Answer: 
Step-by-step explanation:
For this exercise is necessary to remember the following formula:

Where "V" is the speed, "d" is the distance and "t" is the time.
In this case you must solve for the time, then:

Based on the information provided in the exercise, you can identify that:

Therefore, knowing this, you can make the substitution into the formula
.
Through this procedure you get that the equation that can be used to find the amount of hours "h" that it will take Sandra to drive "m" miles at her constant speed, is:
