Answer:
The answer is suppose to be -15.
Step-by-step explanation:
I do not see any statements
I can give you an explanation
Layla forgot to carry the negative
 
        
                    
             
        
        
        
5, 3, 7, 9 are all non-common factors
        
             
        
        
        
It equals 3600 combinations
4(equals the types of cones/cup) x 3(the measures of each one) x 20 (ice cream flavors) x 15 (toppings) += 3600 combinations