Logic Puzzle

Sally is a girl with 3 brothers, meaning there are 3 male siblings in the family.
Each brother has 2 sisters, which refers to the total number of female siblings from the perspective of any brother.
Since Sally is one of these sisters, there must be one additional sister.
Therefore, there are 2 girls in total: Sally and one other sister.

From Sally's perspective, the number of sisters she has is the total number of female siblings minus herself.
With 2 girls in total, Sally has (2 - 1 = 1) sister.

This can be verified by considering the family composition:

• Girls: Sally and one other sister (e.g., Betty).
• Boys: 3 brothers (e.g., Brother1, Brother2, Brother3).
  Sally has 3 brothers, and each brother has 2 sisters (Sally and Betty).
  Thus, Sally has 1 sister.

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