Answer:
A sample of 18 is required.
Step-by-step explanation:
We have that to find our 
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Z-table as such z has a p-value of 
.
That is z with a pvalue of 
, so Z = 1.88.
Now, find the margin of error M as such
In which 
is the standard deviation of the population and n is the size of the sample.
A previous study indicated that the standard deviation was 2.2 days.
This means that 
How large a sample must be selected if the company wants to be 92% confident that the true mean differs from the sample mean by no more than 1 day?
This is n for which M = 1. So
Rounding up:
A sample of 18 is required.
4.5 x 6.2 = 27.9
Hope that helps
Answer:
-3 and -2
Step-by-step explanation:
A better explanation...
(positive)(positive)= positive
(positive)(negative)= negative
(negative)(negative)= positive
(negative)(positive)= negative
Answer:
none of them
Step-by-step explanation:
Two lines are perpendicular when satisfy the next equation: m1*m2 = -1, where m1 and m2 are the slopes o the lines.
line 1:
y – 1 = (x+2)
y = x + 3
slope of line 1 = 1
line 2:
y + 2 = –3(x – 4)
y + 2 =
-3*x + 12
y = -3*x + 10
slope of line 2 = -3
m1*m2 = 1*(-3
) = -3
They are not perpendicular
line 3:
y − 5 = 3(x + 11)
y − 5 = 3*x + 33
y = 3*x + 38
slope of line 3 = 3
m1*m3 = 1*3 = 3
They are not perpendicular
line 4:
y = -3x –
slope of line 4 = -3
m1*m4 = 1*(-3
) = -3
They are not perpendicular
line 5:
y = x – 2
slope of line 5 = 1
m1*m5 = 1*1 = 1
They are not perpendicular
line 6:
3x + y = 7
y = -3x + 7
slope of line 6 = -3
m1*m6 = 1*(-3
) = -3
They are not perpendicular
Answer:
Step-by-step explanation: try to get x in one side and the whole number to another side to get x= blank
