Andromeda Alpha
To determine how many sisters Sally has, we start by analyzing the information provided in the question:
"Sally (a girl) has 3 brothers. Each brother has 2 sisters. How many sisters does Sally have?"
Step 1: Understand the Family Composition
- Sally is a girl.
- She has 3 brothers, which means there are 3 male siblings in the family.
- The key phrase is: "Each brother has 2 sisters."
This tells us that from the perspective of each brother, there are 2 female siblings in the family.
Step 2: Interpret the Meaning of "Each Brother Has 2 Sisters"
- Since Sally is one of the girls in the family, and each brother has 2 sisters, that means there are 2 girls in total in the family.
- One of those girls is Sally, and the other is her sister.
So, the family consists of:
- 3 boys (Sally's brothers),
- 2 girls (Sally and her one sister).
Step 3: Answer the Question
The question is: "How many sisters does Sally have?"
- Sally is a girl, so she doesn't count herself as her own sister.
- There is one other girl in the family — her sister.
Thus, Sally has 1 sister.
Final Answer
$$ \boxed{1} $$
