64. At 0715, on March 9, you pass Knox Landing Gage at mile 313.8 (AHP) and estimate the current will average 3.5 mph for the remainder of the time on the Mississippi River. What is your ETA at the mouth of the Ohio River if you increase speed to turn for 10 mph?

The remaining distance is 640 miles. Subtracting the 3.5 mph current from the 10 mph speed yields a ground speed of 6.5 mph. The travel time is 640 miles / 6.5 mph = 98.46 hours, or approximately 4 days, 2 hours, and 28 minutes. Adding this to the departure time of 0715 on March 9 results in an ETA of 0943 on March 13.