Final answer:
In the Supreme Court of the United States, the minimum number of Justices needed to form a majority opinion is five.
Step-by-step explanation:
In order to form a majority opinion, the minimum number of Justices needed to vote in agreement depends on the size of the court. In the Supreme Court of the United States, for example, there are nine Justices, so the minimum number needed to form a majority is five. This is because a majority is defined as more than half of the total number of Justices. Therefore, if there are an odd number of Justices, the majority is half of the total number rounded up.
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