The inner circle circumference is 18 and the outer is 4
 
        
                    
             
        
        
        
Answer:
x
Step-by-step explanation:
 
        
             
        
        
        
Answer:  
This is the same as writing (n-m)/n
Don't forget about the parenthesis if you go with the second option. 
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Explanation:
The probability that she wins is m/n, where m,n are placeholders for positive whole numbers. 
For instance, m = 2 and n = 5 leads to m/n = 2/5. This would mean that out of n = 5 chances, she wins m = 2 times. 
The probability of her not winning is 1 - (m/n). We subtract the probability of winning from 1 to get the probability of losing. 
We could leave the answer like this, but your teacher says that the answer must be "in the form of a combined single fraction".
Doing a bit of algebra would have these steps

and now the expression is one single fraction.