Williams uses his small motorboat to go 5 miles upstream to his favorite fishing spot. Against the current, the trip takes 1/3 hour. With the current the trip takes 1/5 hour. How fast can the boat travel in still water?

the boat can travel 20 mph in still water.

Step-by-step explanation:

Let x represent the speed of the boat in still water.

Let y represent the speed of the current.

Distance = speed × time

Williams uses his small motorboat to go 5 miles upstream to his favorite fishing spot. Against the current, the trip takes 1/3 hour. The total speed would be (x - y) mph. The distance covered upstream is

5 = 1/3(x - y)

Cross multiplying by 3, it becomes

15 = x - y - - - - - - - - - - - -1

With the current the trip takes 1/5 hour. The total speed would be

(x + y) mph. The distance covered downstream is

5 = 1/5(x + y)

Cross multiplying by 5, it becomes

25 = x + y - - - - - - - - - - - -2

Adding equation 1 to equation 2, it becomes

40 = 2x

x = 20/2 = 20

Substituting x = 20 into equation 1, it becomes

15 = 20 - y

y = 20 - 15

y = 5

4 + 5 7/9= 9 7/9

step-by-step explanation: