During past couple of days, we have looked at using Absolute and Relative Cell References in Excel. You can also use a combination of Absolute and Relative cell references in your formulas. This is called a Mixed Reference. You have the choice of making either the column or the row absolute, such as $D3 (column is absolute, row is relative) or F$6 (column is relative, row is absolute). The row or column preceded by the $ (the absolute reference) would not change when copied or moved, whereas the row or column reference not preceded by the $ (the relative reference) would automatically adjust to its new location.
As an example, suppose you have the following formula in cell D3:
=$B3 * C3
If you copy this formula down to cell E4 (one column to the right and one row down), you would have:
=$B4 * D4
The $B4 portion of the formula contains a Mixed Reference — the row adjusts automatically to the new location (from row 3 to row 4) but the column address will continue to reference column B.

