Answer: The margin of error = 3.71, confidence interval = (354.04, 361.46) and it means that mean cost is lies within the confidence interval.
Step-by-step explanation:
Since we have given that
Sample size = 400
Mean = $357.75
Standard deviation = $37.89
At 95% confidence level, z = 1.96
We first find the margin of error.
Margin of error is given by
95% confidence interval would be
Hence, the margin of error = 3.71, confidence interval = (354.04, 361.46) and it means that mean cost is lies within the confidence interval.
Answer:
96
Step-by-step explanation:
3*4*8=96
Answer:
x and y do not show direct variation.
Step-by-step explanation:
The formula for direct variation is
y = kx Divide each side by y
k = y/x
k should have the same value for every point except, of course, (0,0)
For the first point,
k = 2/(-1) = -2
For the third point,
k = 2/1 = 2
The values of k are different, so x and y <em>do not</em> show direct variation.
I can help you round 206834 and 194268 to its nearest thousands place. 207000 would be the estimate for the first number and 194000 would be the estimate for the second number.