Two cities towards each other were left by two cars. Speed of the first 98km/h, and the second is unknown. In how many hours will they meet if distance between the cities of 1200 km?

Speed of rapprochement 98+ x kmch to find time it is necessary 1200: (98+ x) this expression for calculation of time, but it is necessary to know value or x or time in way. And so the problem is solved only in a general view.
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