## Explanation

This formula uses two named ranges, "range1" (B5:B12) and "range2" (D5:D10).

The core of this formula is the COUNTIF function, which returns a count of each value in both range inside the AND function:

```
COUNTIF(range1,B5) // count in range1
COUNTIF(range2,B5) // count in range2
```

COUNTIF will either return zero (evaluated as FALSE) or a positive number (evaluated as TRUE) for each value in both ranges.

If both counts are positive (i.e. non-zero), the AND function will return TRUE and trigger the conditional format.

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### COUNTIF Function

The Excel COUNTIF function returns the count of cells in a range that meet a single condition. The generic syntax is COUNTIF(range, criteria), where "range" contains the cells to count, and "criteria" is a condition that must be true for a cell to be counted. COUNTIF can be used to count cells...

### AND Function

The Excel AND function is a logical function used to require more than one condition at the same time. AND returns either TRUE or FALSE. To test if a number in A1 is greater than zero and less than 10, use =AND(A1>0,A1<10). The AND function can be used as the logical test inside the IF...