Logic Puzzle

To solve this problem, let's carefully analyze the relationships described.

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Step 1: Understand Sally's Perspective

• Sally is a girl.
• She has 3 brothers.
• So, from her point of view, there are 3 male siblings and herself as a female sibling.

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Step 2: Analyze the Brothers’ Perspective

• The problem states: "Each brother has 2 sisters."
• This means that each of Sally’s brothers sees 2 girls in the family as their sisters.
• Since all the brothers share the same family, the set of sisters they see is the same for all of them.

So, if each brother has 2 sisters, then there are 2 girls in total in the family.

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Step 3: Determine How Many Sisters Sally Has

• Sally is one of those 2 girls.
• Therefore, the other girl is her only sister.
• When we ask "How many sisters does Sally have?", we are not counting herself — we're only counting the other female siblings.

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Final Answer

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