Answer:
1) 102/21
2) 21/51
3) 21/24
Step-by-step explanation:
 
        
             
        
        
        
1.8 - 0.2x = -1.6         Subtract 1.8 on both sides
1.8 - 1.8 - 0.2x = -1.6 - 1.8
-0.2x = -3.4        Divide -0.2 on both sides

x = 17
 
        
             
        
        
        
Answer:
9
Step-by-step explanation:
40 -100 = 60 and 60 percent of 15 is 9