Translate the number 678.625_{10} в hexadecimal like this:
the Integer part of the number is divided by the base of the new number system:
678  16   
672  42  16  
6  32  2  
 A   

the Fractional part of the number is multiplied by the base of the new number system:

0.  625*16 
A  .0*16 
the result of the conversion was:
678.625_{10} = 2A6.A_{16}
the Final answer: 678.625_{10} = 2A6.A_{16}