Question 1205756
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Since the times are the same, the ratio of their speeds is the same as the ratio of the distances, which is 12:10 or 6:5.<br>
Then, since Leo's speed is 1 km/hr faster than Justin's, simple reasoning or formal algebra shows that Leo's speed is 6 km/hr and Justin's is 5 km/hr.<br>
ANSWER: 6 km/hr<br>