Answer:
About 879.877
Step-by-step explanation:
To find f,
f(13) = 45,000(0.9)^13
13f = 45,000(0.25418658283)
13f = 11438.3962274
f = 879.877
Please tell me I did this the right way, Thanks!
 
        
             
        
        
        
Answer:
50
Step-by-step explanation:

 
        
             
        
        
        
75% of 56 is .75 * 56
.75 * 56 = 42
Because you are decreasing, you subtract 42 from 56. 
56 - 42 = 14
A 75% decrease of 56 books would leave 14 books.
        
                    
             
        
        
        
You would write it 2=10(20+2)