A faster way is to select the cell (or range) and 'right click'. This is a convenient way of accessing various frequently used functions.
Notice that selecting 'Format Cells' brings up a submenu that allows you to change the font style size and color. You can also change the formatting to currency ($) or percentage (%).
You can also increase or decrease the number of decimal places (
)
Note that even if you restrict the number of decimal places that are displayed the full accuracy is still used in calculations:
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In the example the value in cell C2 is actually 3.14 but has been formatted to show only 1 decimal place. The calculation shown in cell C3 uses the actual value.