posted by Kiersten Hailey on .
A boat towing a water skier leaves a dock and travels east at a speed of 20mph. Two minutes later, a second boat towing another skier leaves the dock in the same direction at a speed of 25mph. How long will it take the second boat to overtake the first boat?
PLEASE help!? /:
first boat goes for t + 2 min at 20/60
second boat goes for t min at 25/60
distance = same = speed * time
20(t+2)/60 = 25 t/60
4(t+2) = 5 t
8 minutes = t
distance = speed * time
the second boat travels 2 min less than the first boat
converting mph to miles/min, both boats traveled for m minutes, making the same distance.
m * 20/60 = (m-2) * 25/60
20m = 25m - 50
5m = 50
m = 10
10 min at 20mph = 20 * 10/60 = 200/60mi
8 min at 25mph = 25 * 8/60 = 200/60 mi