Make them all have the same denominator
32
25+12 16/32+488/32+124/32+38/32+25/32
Add all of the numerators... to get 691/32+1184/32
1875/32
Simplify to get 58 19/32
        
             
        
        
        
The one next to 3 is 12, the one next to 7 is 28, the one next to 12 is 48. All you have to do is multiply the quads by four and you get the number of wheels.
        
             
        
        
        
Divide it and get 0.6 then multiply by 100 so 60%
        
                    
             
        
        
        
The most common expressions involving 16 and w are:
16+w
16-w
16xw and
16/w
Hope this helps and answers your question