The first table in the screen below is a “question key” and shows how questions in Test A are ordered in the other 3 tests. The second table is an “answer key” that shows the correct answers for all 19 questions in all tests.

Above: Correct answers in I5:K23, formula obscured For example, the answer to question #1 in Test A is C. This same question appears as question #4 in Test B, so the answer to question #4 in Test B is also C. The first question in Test B is the same as question #13 in Test A, and the answer to both is E.

### The challenge

What formula can be entered in I5 (that’s an i as in “igloo”) and copied across I5:K23 to find and display the correct answers for Tests B, C, and D? You’ll find the Excel file below. Leave your answer as a comment below.

### Hints

### Interpretation #1 (incorrect)

C5:E23 shows the same questions from test A, simply reordered. So, for example, in Test B… You can find question #1 from Test A at position #13 You can find question #2 from Test A at position #3 You can find question #3 from Test A at position #7 With the answers to Test A in the array H5:H23, INDEX simply retrieves a value using the number from column C for row number. Doesn’t get much simpler than this. This is not the correct answer for this challenge, but it’s a nice example anyway.

### Interpretation #2 (correct)

The second interpretation is more complicated. C5:E23 is a key that tells you only where you can find a question from test A. It is not reporting a question number, it is reporting an index of sorts. So, for example, in Test B… You can find question #1 from Test A at position #4 You can find question #2 from Test A at position #19 You can find question #3 from Test A at position #2 This is a trickier problem. Instead of telling you what question from Test A is in a given position, the key is telling you where you can find the question you seek. The formula below is one correct answer to this problem, since it will return the answers shown in the original challenge.

Note the mixed references inside MATCH which have been carefully set up to change as needed when the formula is copied across the table. $G5 - column is locked, row will change C$5:C$23 - rows are locked, columns will change Author

### Dave Bruns

Hi - I’m Dave Bruns, and I run Exceljet with my wife, Lisa. Our goal is to help you work faster in Excel. We create short videos, and clear examples of formulas, functions, pivot tables, conditional formatting, and charts.