Supermajority rule gave southern Democrats an effective veto over any presidential nominee for many years, until the rule's abolition at the 1936 Democratic National Convention. A majority vote, or more than half the votes cast, is a common voting basis. Instead of the basis of a majority, a supermajority can be specified using any fraction or percentage which is greater than one-half (i.e., 50%). It can also be called a qualified majority. Common supermajorities include three fifths (60%), two thirds (67%), and three quarters (75%). A two-thirds vote, when unqualified, means two-thirds or more of the votes cast. This voting basis
Fraction (mathematics) follows: To add fractions containing unlike quantities (e.g. quarters and thirds), it is necessary to convert all amounts to like quantities. It is easy to work out the chosen type of fraction to convert to; simply multiply together the two denominators (bottom number) of each fraction. In case of an integer number apply the invisible denominator formula_90 For adding quarters to thirds, both types of fraction are converted to twelfths, thus: Consider adding the following two quantities: First, convert formula_93 into fifteenths by multiplying both the numerator and denominator by three: formula_94. Since formula_95 equals 1, multiplication by formula_95 does