Answer:

Step-by-step explanation:
Since the sample size is quite large, we can use the z-distribution.
The margin of error is given by

Where n is the sample size, s is the sample standard deviation and
is the z-score corresponding to a 90% confidence level.
The z-score corresponding to a 90% confidence level is
Significance level = α = 1 - 0.90= 0.10/2 = 0.05
From the z-table at α = 0.05
z-score = 1.645

Therefore, the margin of error is 0.776.
Answer:
9/4, 3/2, 1, 7/8, 5/8
Step-by-step explanation:
Answer:
x = -2 and y = 2
Step-by-step explanation:
We have the following system of linear equations;
y=x+4
y=-2x-2
To solve the above system, we shall be equating the right hand sides of the two equations since we have y's on the left hand side of both equations;
x + 4 = -2x - 2
add 2x on both sides of the equation;
x + 4 + 2x = -2x - 2 + 2x
3x + 4 = -2
subtract 4 on both sides of the equation;
3x + 4 - 4 = -2 - 4
3x = -6
x = -2
We can use the first equation y=x+4 to determine the value of y;
y = -2 + 4
y = 2
The solution to the system of linear equations is thus;
x = -2 and y = 2
Answer:
About 9% or 0.09
Step-by-step explanation: