CEMC Euclid, 2009

Number theory Difficulty 3.0 AMC 10/12 Prove it Canada

Alice drove from town $E$ to town $F$ at a constant speed of $60$ km/h. Bob drove from $F$ to $E$ along the same road also at a constant speed. They started their journeys at the same time and passed each other at point $G$ . Alice drove from $G$ to $F$ in $45$ minutes. Bob drove from $G$ to $E$ in $20$ minutes. Determine Bob's constant speed.

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