A kayak moves at a rate of 12 mph in still water. If the rivers current flows at a rate of 5mph how long does it take the boat to travel 23 miles upstream?
so the effective rate = 12-5 or 7 mph
time = 23/7 = 3.2857 hrs
= 3 hrs and appr 17 minutes
To find out how long it takes for the kayak to travel 23 miles upstream, we need to take into account its speed in still water and the speed of the river's current.
When traveling upstream, the current acts against the boat's motion, reducing its effective speed. So, to determine the kayak's speed relative to the ground when moving upstream, we need to subtract the speed of the river's current from its speed in still water.
Speed of the kayak upstream = Speed in still water - Speed of the river's current
= 12 mph - 5 mph
= 7 mph
Now that we know the speed of the kayak when moving upstream, we can calculate the time it takes to travel the given distance of 23 miles using the formula:
Time = Distance / Speed
Time = 23 miles / 7 mph
Time = 3.286 hours
Therefore, it takes approximately 3.286 hours (or 3 hours and 17 minutes) for the kayak to travel 23 miles upstream.