Answer:
  -6.75 + (10.25)    =  ( (-6)  + (10))  + ( (-0.75) + (0.25))
Here, the integer part  =     ( (-6)  + (10))
Decimal part =   ( (-0.75) + (0.25))
Step-by-step explanation:
Here, the given expression is:    -6.75 + (10.25)
Now,  -6.75  = (-6)  +  (-0.75)
Also, (10.25)  = (10)  + (0.25)
So, the expression can be written as 
  -6.75 + (10.25)  =  (-6)  +  (-0.75) +  (10)  + (0.25)
                            = ( (-6)  + (10))  + ( (-0.75) + (0.25))
or,   -6.75 + (10.25)    =  ( (-6)  + (10))  + ( (-0.75) + (0.25))
Where the integer part is    ( (-6)  + (10))
and the decimal part is  ( (-0.75) + (0.25))