Answer :
If the purchase was 240, and the tax was 12, the 12/240=.05 or 5%
If the total purchase was 240, the subtract 12 from 240, and 12/ 228=.0526 or 5.26%
If the total purchase was 240, the subtract 12 from 240, and 12/ 228=.0526 or 5.26%