In Microsoft Excel, you can format a cell containing the sum of amounts of time that exceed 24 hours with the number format "[h]:mm:ss"; Microsoft Excel automatically adds times beyond 24 hours and formats them correctly.
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<li>To add times with a sum that exceeds 24 hours, use a normal sum formula: =SUM(Range)</li>
<li>Then, click <strong>Cells</strong> on the <strong>Format</strong> menu, click the <strong>Number</strong> tab, click <strong>Custom</strong> in the <strong>Category<span style="background-color: #ffff00;"> </span></strong><span style="background-color: #ffff00;">[h]:mm:ss<br /></span></li>
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<div class="sbody">This format works correctly with times that exceed 24 hours.</div>
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<strong>Note:</strong> Range is either the defined name of a range that contains the times or the cell reference of the range that contains your times (for example, A1:A4). The values in the range must be in the "h:mm" or "hh:mm" format.
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<div class="sbody">(from <a href="http://support.microsoft.com/kb/190633">http://support.microsoft.com/kb/190633</a>)</div>
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