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.
Answer:
x= 1, y=3
Step-by-step explanation:
y= 2x +1
y= -x +4
Those two equation are in a system that means they need to be true in the same time. Just like I would say look for a car that is red and is a truck in this case we look for x and y is true that y = 2x+1 and is true that y= =x+4.
so y= 2x+1 but y is -x+4 so substitute
-x+4 = 2x +1, add x on both sides
4= 2x+x +1, subtract 1 from both sides
4-1 = 2x +x, combine like terms
3 = 3x , divide both sides by 3
x=1
if x=1 we substitute in y= -1 +4 = 3
Answer:
75
Step-by-step explanation:
We have a 90 degree angle and a 15 degree angle that add up to 105. The angle that is missing can be found by doing 180 - 105 = 75 (since it's a straight line). X is vertical from the 75 degree angle, so 75 is your answer.


Coordinates of the point C is: (-4.1, -2.5)
X + y = 4
Is how you would write it in standard form.