Answer:
9.) 
10.) 
11.) 
minutes of calling would make the two plans equal.
12.) Company B.
Step-by-step explanation:
Let <em>t</em> equal the total cost, and <em>m,</em> minutes.
Set up your models for questions 9 & 10 like this:
<em>total cost = (cost per minute)# of minutes + monthly fee</em>
Substitute your values for #9:
Substitute your values for #10:
__
To find how many minutes of calling would result in an equal total cost, we have to set the two models we just got equal to each other.
Let's subtract 
from both sides of the equation:
Subtract 
from both sides of the equation:
Divide by the coefficient of 
, in this case: 
__
Let's substitute 
minutes into both of our original models from questions 9 & 10 to see which one the person should choose (the cheaper one).
Company A:
Multiply.
Add.
Company B:
Multiply.
Add.
<em />
Answer:
the answer is A
Step-by-step explanation:
casue i said so
Subtract the 2x and divide by -4. y=1/2x-2 or y=x/2-2
Answer:
38.46%
Step-by-step explanation:
There are no names or marking that can make the calculator look different, so the order is not important. Then we should use a combination to solve this problem.
There are 40 calculators in one shipment, 37 of them good items and 3 of them are defect items. We need to choose 19 good calculators and 1 defect calculator. The number of ways to do that will be:
* 
= 37!
= 53017895700
The number of possible ways to choose 20 calculators out of 40 calculators will be:
= 
=137846528820
The chance will be: 53017895700/ 137846528820 = 0.3846= 38.46%
The anwser to the problem is C.
