Rule of 25 Percent Tip http://www.numsum.com/spreadsheet/show/50910 Wed, 05 Sep 2007 16:52:19 GMT Input $1.00: 7.00%<br/> Menu Cost: Enter Your Local Tax Wed, 05 Sep 2007 16:52:19 GMT http://www.numsum.com/spreadsheet/show/50910 Output $1.00: 16.8%<br/> Menu Cost: Tip %, based on rule of 25% Wed, 05 Sep 2007 16:52:19 GMT http://www.numsum.com/spreadsheet/show/50910