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:
p(7) = 57
Step-by-step explanation:
Because this is a function, all you have to do is input 7 for x like so:
p(x)=x^2+x+1 ---------------> p(7)=7^2+7+1
so 49 + 8
= 57
Answer:10,950=350x+475y
X=trumpet
Y=trombone
Step-by-step explanation:
Mathematically written:
3 * x + 7 = 25
3x + 7 = 25
3x = 25 - 7
3x = 18
x = 18 / 3
x = 6
Proof:
3 * 6 + 7 = 25
18 + 7 = 25
25 = 25 → both sides of the equation are equal, our answer is correct
Notes:
A number - Is an unknown number, called a variable, which in this case is substituted by the letter x.
Hope it helped,
BioTeacher101
