Use the Fraction format to display or type numbers as actual fractions, rather than decimals.
 Select the cell or range (range: Two or more cells on a sheet. The cells in a range can be adjacent or nonadjacent.) of cells that you want to format.
How to select a cell or a range
To select 
Do this 
A single cell 
Click the cell, or press the arrow keys to move to the cell. 
A range of cells 
Click the first cell of the range, and then drag to the last cell, or hold down SHIFT while you press the arrow keys to extend the selection.
You can also select the first cell of the range and then press F8 to extend the selection by using the arrow keys.

A large range of cells 
Click the first cell in the range, and then hold down SHIFT while you click the last cell in the range. You can scroll to make the last cell visible. 
All cells on a worksheet 
Click the Select All button.
To select the entire worksheet, you can also press CTRL+A.
Note If the worksheet contains data, CTRL+A selects the current region. Pressing CTRL+A a second time selects the entire worksheet.

Nonadjacent cells or cell ranges 
Select the first cell or range of cells, and then hold down CTRL while you select the other cells or ranges.
You can also select the first cell or range of cells and then press SHIFT+F8 to add another nonadjacent cell or range to the selection.
Note You cannot cancel the selection of a cell or range of cells in a nonadjacent selection without canceling the entire selection.

An entire row or column 
Click the row or column heading.
Row heading
Column heading
You can also select cells in a row or column by selecting the first cell and then pressing CTRL+SHIFT+ARROW KEY (RIGHT ARROW or LEFT ARROW for rows, UP ARROW or DOWN ARROW for columns).
Note If the row or column contains data, CTRL+SHIFT+ARROW KEY selects the row or column to the last used cell. Pressing CTRL+SHIFT+ARROW KEY a second time selects the entire row or column.

Adjacent rows or columns 
Drag across the row or column headings. Or select the first row or column; then hold down SHIFT while you select the last row or column. 
Nonadjacent rows or columns 
Click the column or row heading of the first row or column in your selection; then hold down CTRL while you click the column or row headings of other rows or columns that you want to add to the selection. 
More or fewer cells than the active selection 
Hold down SHIFT while you click the last cell that you want to include in the new selection. The rectangular range between the active cell (active cell: The selected cell in which data is entered when you begin typing. Only one cell is active at a time. The active cell is bounded by a heavy border.) and the cell that you click becomes the new selection. 
Note To cancel a selection of cells, click any cell on the worksheet.
 On the Format menu, click Cells.
 On the Number tab, click Fraction in the Category list.
 In the Type list, click the fraction format type that you want to use.
Available fraction formats
Fraction format 
This format displays as 
Singledigit fraction 
123 1/2, rounding to the nearest singledigit fraction value 
Doubledigit fraction 
123 26/57, rounding to the nearest doubledigit fraction value 
Tripledigit fraction 
123 57/125, rounding to the nearest tripledigit fraction value 
Fraction as halves 
123 1/2 
Fraction as quarters 
123 2/4 
Fraction as eighths 
123 4/8 
Fraction as sixteenths 
123 7/16 
Fraction as tenths 
123 5/10 
Fraction as hundredths 
123 46/100 
Notes
 After you apply a fraction format to a cell, decimal numbers as well as actual fractions that you type in that cell will be displayed as a fraction. For example, typing .5 or 1/2 results in 1/2 when the cell has been formatted with a fraction type of Up to one digit.
 If no fraction format is applied to a cell, and you type a fraction such as 1/2, it will be formatted as a date. To display it as a fraction, apply a Fraction format, and then retype the fraction.
 If you don't need to perform calculations on fractions, you can format a cell as Text before you type a fraction into it (Format menu, Cells command, Number tab). This way, the fractions that you type will not be reduced or converted to decimals. However, you cannot perform mathematical calculations on fractions that are displayed as text.
 To reset the number format of a selected cell or range, click General in the Category list. Cells that are formatted with the General format have no specific number format.