To buy 700 kilometers which are not finding at distance there were at 7:00 in the morning towards each other a motor ship and the barge the meeting took place at 21:00 the same day the motor ship went with a speed of 30 km of h With what speed there was an exchange

The barge of a yshl z_ shvidk_styu 20 km/Thu to. the meeting took place in 14 hours, the motor ship floated 14*30=420 km, and barge 700-420 = 280 km, 280:14=20 km/h
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