Answer:

And the best answer on this case would be:
b) m = 4.635
Step-by-step explanation:
Let X the random variable of interest and we know that the confidence interval for the population mean
is given by this formula:

The confidence level on this case is 0.9 and the significance 
The confidence interval calculated on this case is 
The margin of error for this confidence interval is given by:

Since the confidence interval is symmetrical we can estimate the margin of error with the following formula:

Where Upper and Lower represent the bounds for the confidence interval calculated and replacing we got:

And the best answer on this case would be:
b) m = 4.635
Answer:
Step-by-step explanation:
The correct question is
Zena needs a salesperson. Salesperson A is offering his services for an initial $50 in addition to $5 per hour. salesperson B is offering her services for an initial $40 in addition to $7 per hour. When will the two coaches charge the same amount of money?
Let
x ----> the number of hours
y ----> the total charge
we know that
Salesperson A
------> equation A
Salesperson B
------> equation B
To find out when the two coaches charge the same amount of money, equate equation A and equation B and solve for x
7x+40=5x+50
7x-5x=50-40
2x=10
<h2>x=5 hours i think just im not sure but i tried</h2>
Answer: 7x^2 + 2x + 7
Step-by-step explanation:
Combine likes terms that have alike variables and alike exponents.
(3x^2 + 4x^2) + (2x) + (2 + 5)
7x^2 + 2x + 7