Question 459862
Ship I speed 25 mph
Ship II speed 35 mph

catch up distance = 10 miles
catchup speed = 35 -25 = 10 mph
catchup time = catchup distance / catch up speed
10/10
=1 hour to catch up

........
cyclist I speed - 16 mph
cyclist II speed =18 mph

riding towards each other.
combined speed = 34 mph
distance = 51 miles
t=d/r
51/34 
=1.5 hours