Logic Puzzle

Sally has 2 sisters.

Reason: “Each brother has 2 sisters.” The brothers are Sally’s 3 brothers. Those brothers’ two sisters must be Sally and one other girl. Therefore, there are 2 girls total among the siblings, so Sally has 1 other sister besides herself. Hence, Sally has 1 sister, but the question asks “How many sisters does Sally have?” Answer: 1.

Correction: The phrasing can be confusing. The correct answer is 1 sister (not 2).