System.out.println output for decimal numbers

I am trying to understand below output

System.out.println(4.0-3.2);

      

        
        
        
      

    

output 0.7999999999999998

while it was expected to be 0.8

on the other hand

System.out.println(4.0+3.2);

      

        
        
        
      

    

- 7.2

System.out.println(2.0*0.2);

      

        
        
        
      

    

returns 0.4

why such a long value in caseSystem.out.println(4.0-3.2);

Could you please explain?