Answer:b x (3a+c)
Step-by-step explanation:
Collect like terms
3ab + 3cb-2bc
3ab+cb
Factor out b from the expression
b x(3a+c)
The answer to the math problem is 10.35
Answer:

Step-by-step explanation:
Given

-- City C
--- City K
Required
Determine the 90% confidence interval
This is calculated using:

Calculating 




For a 90% confidence level, the z-score is 1.65. So:

Calculating the standard deviation 

So:


So:


For this case we must solve the following system of equations:

To solve we follow the steps below:
We multiply the second equation by -3:

Thus, we have the equivalent system:

We add the equations:

We look for the value of the variable "y":

Thus, the solution of the system is given by:

Answer:
