Rows — In a row of 30 students facing North, what is R's position from the left end? Statements: I. There are 12 students between R and Q. II. T is 10th from the right end; there are 16 students between T and R.

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Solve this multiple-choice question and choose the correct option.

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Introduction / Context:Compute an absolute position using a fixed-size row and separations. Given Data / Assumptions: Total = 30 students. I: Only distance between R and Q (no anchors). II: T is 10th from right; 16 between T and R. Concept / Approach:Convert T's right-rank to a left-rank, then apply the 'k between' offset (k+1) and validate side feasibility. Step-by-Step Solution: From II: T's left-rank = 30 − 10 + 1 = 21.If R is to the right of T: R = 21 + 16 + 1 = 38 (invalid > 30). Hence R must be to the left: R = 21 − 16 − 1 = 4.Thus R is 4th from the left. Statement I alone has no absolute anchor and is insufficient. Verification / Alternative check:Bound checks ensure only the left-side placement is feasible, giving a unique result. Why Other Options Are Wrong: A/C/D/E: II alone already yields a unique position. Common Pitfalls:Forgetting to test both sides; forgetting the +1 offset. Final Answer:B — Statement II alone suffices (R = 4th from left).

Rows — In a row of 30 students facing North, what is R's position from the left end? Statements: I. There are 12 students between R and Q. II. T is 10th from the right end; there are 16 students between T and R.

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