Y = -3x + 6....the slope here is -3. A parallel line will have the same slope.
y = mx + b
slope(m) = -3
(-4,7)....x = -4 and y = 7
now we sub into the formula and find b, the y int
7 = -3(-4) + b
7 = 12 + b
7 - 12 = b
-5 = b
so ur parallel equation is : y = -3x - 5 <==
Relative dating is the answer
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.