Final answer:
The term is a quorum, which is usually a simple majority of legislative body members that must be present to conduct business. A supermajority, which is more than a majority, is required for specific important actions.
Step-by-step explanation:
The term for the minimum number of representatives that must be present to permit a legislative body to take official action is a quorum. To do business, each chamber of a legislative body, such as the U.S. Congress, needs a quorum, which is typically a simple majority of its members. While a full majority need not vote, they must be present and capable of voting. However, in some cases, more than a simple majority is required to pass legislation or take certain actions. This is known as a supermajority, a given proportion of a voting body greater than 50 percent. Situations requiring a supermajority include amending the constitution, calling early elections, and the impeachment process, among others.