Two settlements were left at the same time towards each other by two riders. the first speeded at 200 meters per minute and the second passed in a minute and 20 meters are less. riders met in 50 minutes. find distance between settlements.

200-20=180m/mines - the speed of the second rider, 200*50=10000m =10 km - were passed by the first rider, 180*50=9000m =9 km - were passed by the second rider, 10+9=19 km - distance between settlements.
Answer add