Answer:
9.009
Step-by-step explanation:
As a mixed number, it is 9 9/1000.
The "thousandths" place in a decimal number is the third digit to the right of the decimal point, so a 9 in that place signifies 9 thousandths, or 9/1000. Adding 9 units gives ...
9 9/1000 = 9 + 0.009 = 9.009
