Difficulty: Easy
Correct Answer: 1,100 m
Explanation:
Introduction / Context:
When a faster runner gives a head-start but still aims to finish together, the time equality relates the full distance for the faster to the reduced distance for the slower via their speed ratio.
Given Data / Assumptions:
Concept / Approach:
Equal finish times: L / vA = (L − 300) / vB. Substitute vA and solve for L.
Step-by-Step Solution:
Verification / Alternative check:
Times become equal: A’s time = 1,100 / (11/8 vB) = 800 / vB; B’s time = 800 / vB.
Why Other Options Are Wrong:
Other lengths do not satisfy the derived equality.
Common Pitfalls:
Subtracting 300 from the faster runner’s distance, or inverting the 11/8 ratio.
Final Answer:
1,100 m
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