Difficulty: Easy
Correct Answer: 800 m
Explanation:
Introduction / Context:Relative speed chase problems compare how quickly a pursuer closes the gap on a target when both move simultaneously. Here, movement is in “leaps per minute,” but we convert each to metres per minute to compute the catch-up distance cleanly.
Given Data / Assumptions:
Concept / Approach:The time to catch equals initial lead / relative speed. Relative speed (tiger w.r.t. deer) = tiger speed − deer speed.
Step-by-Step Solution:
Tiger speed = 5 * 8 = 40 m/minDeer speed = 4 * 5 = 20 m/minRelative speed = 40 − 20 = 20 m/minInitial gap = 50 * 8 = 400 mTime to catch = 400 / 20 = 20 minDistance run by tiger until catch = tiger speed * time = 40 * 20 = 800 mVerification / Alternative check:If both run 20 min, the deer covers 20 * 20 = 400 m; adding to the tiger’s initial deficit of 400 m confirms equality at the catch point (tiger total 800 m vs deer total 400 m after the head start).
Why Other Options Are Wrong:
Common Pitfalls:Using leaps/min directly without converting to m/min, or misreading “50 leaps” as metres. Another mistake is adding speeds instead of taking the difference for same-direction chase problems.
Final Answer:800 m
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