A mixed cell reference is a combination of relative and absolute cell references. In spreadsheets, cell references are used in a variety of commands, charts, functions and formulas.
In Microsoft Excel, there are three types of cell references: relative, absolute and mixed. Cell references are relative by default. This means that when a formula is copied from one cell to another cell or multiple cells, it changes to match the cell reference of the new cells. For instance, when users copy the formula = A3+B3 from cell C3 to cell C4, the formula in C4 will adjust one cell down to = A4+B4. If users want to keep the original cell reference after copying the formula, they place the $ sign in front of the columns (A and B) as well as row 3, which becomes (=$A$3+$B$3). This is called an absolute reference.
An absolute reference remains the same when a formula is copied from one cell to another cell or cells.
Although it is rare to use mixed cell references, the need may arise when users need to make a cell reference mixed. In that case, they lock either the row or the column by preceding it with the $ sign as in $A3 or B$3.
It is a cell reference that has either the row or column made absolute, but not both, using the dollar sign. A1 is relative. $A1 is mixed. A$1 is mixed. $A$1 is absolute.
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1. Doubleclick the spreadsheet you want to open. This opens it in the native program Microsoft Excel. 2. Click on the cell with the reference to another cell. 3. Click on the textbox
http://www.ehow.com/how_8161990_deletecellrefere...

1. PLACE all numbers that you update regularly on their own sheet tab. Ad. 2. REFERENCE those numbers using the following methods. TYPE " to start a formula in the cell and navigate
http://www.wikihow.com/UseCellReferences

There are four variations of cell references. Relative  neither the column or row is fixed (so if you copy over or down in the spreadsheet from this type of cell reference in a formula
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