I actually did this problem today for edge , I included a picture that I used to understand how to do this problem the answer is 1%.
 
        
        
        
Step-by-step explanation:
I would say  the one that says after eliminating a variable,the result is x=0
cause the zero can change into any number.
 
        
             
        
        
        
Sry if i’m wrong but i’m pretty sure he can spend $200 since you alr take out 30.
        
                    
             
        
        
        
Răspuns:
100%
Explicație pas cu pas:
Permiteți numărul inițial de fotografii = x
x - 50% din x = x - 0,5x = 0,5x
0,5x + câte% din 0,5x = x
x - 0,5x = y% de 0,5x
0,5x / 0,5x = 1
Prin urmare,
100% = 1
Prin urmare, x trebuie mărit cu 100% pentru a reveni la numărul original.