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UKMT Pink Kangaroo, 2022

Algebra Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

A rabbit and a hedgehog participated in a running race on a $550$ m long circular track, both starting and finishing at the same point. The rabbit ran clockwise at a speed of $10$ m/s and the hedgehog ran anticlockwise at a speed of $1$ m/s. When they met, the rabbit continued as before, but the hedgehog turned round and ran clockwise. How many seconds after the rabbit did the hedgehog reach the finish?

(A) $25$ (B) $45$ (C) $50$ (D) $55$ (E) $100$

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