DeepSeek V3.2 Exp
Let's go step by step.
Step 1: Identify Sally's family from her point of view
Sally is a girl.
She has 3 brothers.
So there are 3 boys in the family and Sally (1 girl so far).
Step 2: Consider the statement "Each brother has 2 sisters"
From a brother's perspective, his sisters are all the girls in the family except himself (since he’s a boy).
If each brother has 2 sisters, that means there are 2 girls in the family total, from the brother’s point of view.
Step 3: Determine the number of girls
We already know Sally is one of these girls.
If there are 2 girls total, then Sally has 1 sister.
Step 4: Conclusion
Sally has 1 sister.
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