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Step-by-step explanation:
For 1. 7/8 is 90 percent so .90
For 2+. Add the bottom together, whatever you get divide top by bottom.
The others you just divide them by each other.
 
        
             
        
        
        
2x/3 - 5 = 21
2x/3 = 26
2x = 78
x = 39
OPTION A is the answer.....
 
        
                    
             
        
        
        
Answer:
<h2>А. 3, 5, 7</h2><h2 />
Step-by-step explanation:
Because 
7 - 3 = 4
7 + 3 = 10
then
7 - 3 < 5 < 7 + 3
the 3 other cases don’t fit with this rule.