What are two other form for 8.517

Give the 2 form of 8.517
This given number is a decimal number, where 8 is the whole number and .517 are on a decimal point.
Now, what are the 2 forms of this given number
First form
=> 8.517 = 8 + 517/1 000 if your divide 517 by 1000 the answer is .517, then add it with 8
second form
=> 8.517 = 8 517/1 000, if you divide 8 517 by 1000 the answer will be 8.517

Ibelieve the total for the tip could be $21.90

I’m having a hard time understanding your question