Well-being of primary schools have a 200-long circular runway

well-being of primary schools have a 200-long circular track, Dongdong and Jingjing the same time, starting from the starting point in the same direction, Dongdong 6 meters per second, run, run Jingjing 4 meters per second. Dongdong for the first time when the duo was running to catch up with Jingjing how many meters? Jingjing the second time two months to run to catch up with the number of laps?

To formula! !

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for the first time: 200 / (6-4) = 100 seconds

Dongdong: 100 * 6 = 600M

Jingjing: 100 * 4 = 400M

No. Secondary: 200 / (6-4) = 100 seconds

Dongdong: 100 * 6 * 2 = 1200M 1200/200 = 6 circles

Jingjing: 100 * 4 * 2 = 800M 800/200 = 4 lap

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