The answer is C
By the way, that expression means "n choose k". Hope I helped!
        
                    
             
        
        
        
Answer:
D. The McCarter's must make more than 10 visits to the pool for the pass to be a better deal.
Step-by-step explanation:
First, I chose the option that seemed most likely. Once I chose D, I plugged in the answer to see if it actually worked. 
10 x 7.5 =75 dollars + 50 (pass fee) = 125 dollars total. 
10 x 12.5= 125 dollars. 
Therefore, in order to get a deal off of the seasonal pass, the McCarter's would have to visit the pool more than 10 times. D.
 
        
             
        
        
        
The first choice can be any one of the 8 side dishes.
               For each of these . . .
The 2nd choice can be any one of the remaining 7.
     Total number of ways to pick 2 out of 8 = (8 x 7) = 56 ways .
BUT ...
That doesn't mean you can get 56 different sets of 2 side dishes.
For each different pair, there are 2 ways to choose them . . .
(first A then B), and (first B then A).  Either way, you wind up with (A and B).
So yes, there are 56 different 'WAYS' to choose 2 out of 8.
But there are only 28 different possible results, and 2 'ways'
to get each result.
        
                    
             
        
        
        
Answer:


Step-by-step explanation:
Let


Currently:

Two years ago

Required
H and B
We have:

Open bracket

Add 2 to both sides


Substitute 

Collect like terms


Substitute  in
 in 


