Rodney and Todd are rowing down a river that is 50 yards wide at one end. If the river's width increases from this end uniformly by 2 yards every 10 meters along, and they row along the river at a rate of 5 m/s, how long (in seconds) will it take them to get to the point where the river is 80 yards wide?
How many yards wider is the river at their destination? ** The difference in width between where they're starting from and their destination is 80-50 = <<80-50=30>>30 yards
How many meters do they have to cover? ** The width increases 2 yards every 10 m along the river so they would have to cover (30/2)*10 = <<(30/2)*10=150>>150 meters
How long will it take him to cover the 150 meters? ** Traveling at the rate of 5m/s, he will spend 150/5 = <<150/5=30>>30 seconds
#### 30