Are the numbers manually entered in Word? Or is it a numbered list. Click in the list in Word and hit Enter/Return and start typing, see if the paragraph gets the next number.
I'm guessing it's a numbered list in Word (most Word users know how to click the Number or Bullet button at the top to make an auto-numbered or bulleted list) and when you're pasting it in, you're losing the autonumbering, they're being converted to manual numbers followed by a tab.
To confirm and fix this: go to InDesign Preferences, and in the Clipboard Handling section at the bottom, see if you have "Text Only" selected under the "When Pasting Text and Tables." If so, that's what is causing the double-hit of numbers. It's converting Word's auto-numbered to text numbers.

Solution is to either:
- Switch the Preference to "All information" when Pasting, which will bring in the list as an autonumbered Word style, and when you apply your own paragraph style, will simply switch to your/InDesign's autonumbering, OR
- In Word, select the paragraphs and turn off the Autonumber attribute for them before you copy the text.
If the Word user actually did enter manual numbers, then the best solution is to use the GREP cleanup after pasting into ID, as described above.
AM