Here's link to the answer:
cutt.us/tWGpn
 
        
             
        
        
        
Answer:
510
Step-by-step explanation:
(0.68)750
shift decimal places
510.00
refine:510
 
        
             
        
        
        
A rational number would be 81/10 or 8.1
        
             
        
        
        
<span>To solve this problem you must apply the proccedure shown below:
 1. You have the following information given in the problem above:
 - There are 75 classmates.
 - 56% of his 75 classmates like salsa music and 80% of his 60 relatives like salsa music.
 2. Therefore, you have:
 - Number of his classmates that likes salsa music:
 75x0.56=42 
 - Number of his r</span>elatives that like salsa music:
 60x0.80=48
 3. Then you have:
 48-42=6
 Therefore, the answer is: 6.