Click A16.
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Click the Insert Function button on the Formula bar.
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Type a brief description that describes what you want to do in the Search for a function box.
Then click Go.
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If necessary, click a function category you want to use.
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Click the function you want to use.
Click OK.
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Enter the cell addresses in the text boxes.
Or click the Collapse Dialog button to the right of the text box
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Select the cell or range using your mouse.
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And then click the Expand Dialog button.
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Click OK.
