Nancy rowed across the lake with her friend Kelly at a rate of 5 mph. Kelly then rowed back at a rate of 4 mph. If the lake is 6 miles across, how long did it take them to complete their trip?
it would be 1.2 hours or 72 minutes to go forward 5 mph and it would 1.5 hours or 90 minutes to go backward 4 mph so it would take 2.7 hours hope this helps :)
