In a symbolic family notation, "A + B" means A is the father of B, "A − B" means A is the mother of B, "A * B" means A is the brother of B, and "A % B" means A is the sister of B. Given the expression "P + Q * R − S", how is Q related to S?

Introduction / Context:
This question uses symbolic notation to represent family relations. Each operator has a specific meaning, and the expression "P + Q * R − S" combines several operators. We are asked to find how Q is related to S. Questions like this appear regularly in reasoning tests and require careful interpretation of both the order and the meaning of the symbols.

Given Data / Assumptions:
• "A + B" means A is father of B.• "A − B" means A is mother of B.• "A * B" means A is brother of B.• "A % B" means A is sister of B.• The expression is "P + Q * R − S".• Operators connect people pairwise from left to right when interpreted.

Concept / Approach:
We interpret each operator step by step. First, "Q * R" means Q is brother of R. Next, "R − S" means R is mother of S. The relation "P + Q" establishes that P is father of Q but is not directly needed to answer how Q is related to S. Once we know R is the mother of S and Q is brother of R, we can see that Q is the maternal uncle of S. The uncle relation is exactly what is represented in the options by uncle of S.

Step-by-Step Solution:
Step 1: Interpret "Q * R". This tells us that Q is brother of R.Step 2: Interpret "R − S". This tells us that R is mother of S.Step 3: From step 2, S is child of R, and R is female.Step 4: From step 1, Q and R are siblings, with Q male (brother).Step 5: A male sibling of a child's mother is the child's maternal uncle.Step 6: Therefore Q is the uncle of S.Step 7: The segment "P + Q" simply tells us that P is father of Q and does not change the relation between Q and S.

Verification / Alternative check:
Consider a small family where P has a son Q. Q has a sister R. R is the mother of S. The roles fit "P + Q * R − S". In that structure, Q is uncle of S. No other standard relation such as brother or father can hold between Q and S without contradicting the mother relationship between R and S and the sibling relationship between Q and R.

Why Other Options Are Wrong:
Husband of S: This would require a spousal link, which is not mentioned.Brother of S: A brother would share parents with S, but Q is sibling of S's mother, not of S.Father of S: The father would be the husband of R, not the brother of R.Cousin of S: Cousins are children of siblings, but Q and R are siblings, and S is child of R, not child of Q.

Common Pitfalls:
One common mistake is to misinterpret the order of operations and attach the wrong relation to the wrong pair. Another is to forget that Q * R fixes Q as a sibling of R, not as a spouse. Always interpret each operator carefully and construct the family links slowly to avoid misclassifying the relationship.

Final Answer:
Q is the uncle of S.