I think I understand the problem now.
When you create a cross-workbook formula by pointing and clicking, you get a formula like this: =[workbook1.xlsx]Sheet1!$B$2
This represents the absolute reference $B$2. Because it's an absolute reference, it will not change when you AutoFill it down the column. In order to allow it to AutoFill, you need to change the formula to: =[workbook1.xlsx]Sheet1!$B2
You can find a complete explanation of absolute and relative references in the video tutorial: Essential Skills Lesson 3-13 Understand mixed cell references.
- Open both workbooks.
- View the workbooks side by side by clicking View > Window > Arrange All > Vertical.
This isn't strictly necessary, but it makes it easier to create the formulas.
Using Arrange All is covered more extensively in the video lesson: Essential Skills Lesson 2-2 Create a new workbook and view two workbooks at the same time.
- Click in cell C2 in the Workbook2 window (the first cell in the empty SNN column).
- Press the = key to start a formula.
- Click in cell B2 in the Workbook1 window (the first of the populated SNN numbers).
You should see the formula: =[workbook1.xlsx]Sheet1!$B$2
- Modify the formula to: =[workbook1.xlsx]Sheet1!$B2
- Click and drag the AutoFill handle from cell C2 to the bottom of column C.
As you can see, the numbers are shown correctly.
For more on how to use AutoFill, see: Essential Skills Lesson 2-17 Speed up your AutoFills and create a custom fill series.
If you follow these steps on your exam, the formulas should work correctly. If they don't, there must be some unusual feature of the workbook that you are working on, although I can't think of any that should prevent this from working. Please let me know if you do figure out the cause, as it would be useful information if this question comes up again in the future.
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