Answer:
a) 17.09 hours
b) The 95% confidence interval estimate of the population mean flying time for the Pilots is between 31.91 hours and 66.09 hours
Step-by-step explanation:
We have the standard deviation of the sample, so we use the t distribution to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 49 - 1 = 48
95% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 48 degrees of freedom(y-axis) and a confidence level of 
. So we have T = 2.0106
The margin of error is:
M = T*s = 2.0106*8.5 = 17.09
s is the standard deviation of the sample. 17.09 hours is the answer for a.
The lower end of the interval is the sample mean subtracted by M. So it is 49 - 17.09 = 31.91 hours
The upper end of the interval is the sample mean added to M. So it is 49 + 17.09 = 66.09 hours
The 95% confidence interval estimate of the population mean flying time for the Pilots is between 31.91 hours and 66.09 hours
The new parking lot must hold twice as many cars as the previous parking lot. The previous parking lot could hold 56 cars. So this means the new parking lot must hold 2 x 56 = 112 cars
Let y represent the number of cars in each row, and x be the number of total rows in the parking lot. Since the number of cars in each row must be 6 less than the number of rows, we can write the equation as:
y = x - 6 (1)
The product of cars in each row and the number of rows will give the total number of cars. So we can write the equation as:
xy = 112 (2)
Using the above two equations, the civil engineer can find the number of rows he should include in the new parking lot.
Using the value of y from equation 1 to 2, we get:
x(x - 6) = 112 (3)
This equation is only in terms of x, i.e. the number of rows and can be directly solved to find the number of rows that must in new parking lot.
Answer:
A, B
Step-by-step explanation:
A. 12/3=4
B. 4/1=4
C. 6/4=1 1/2
D. 4/6=2/3
Answer:
y=2x+5
Step-by-step explanation:
y=2x+4 means that the slope is m1=2
A parallel line shall have the same slope so
m2=m1=2
Therefore, the equation of the new line will be
y=2x+q
where q is the y-intercept, that is 5 because the line must pass in (0,5), so
q=5
and
y=2x+5
