Question

Paulina swims 5 miles down a creek with a current for 2 hours. It takes her 4

Answer 1

Answer: her swimming speed = 1.875 mph

Speed of current = 0.625 mph

Step-by-step explanation:

Let x represent her swimming speed.

Let y represent the speed of the current.

Paulina swims 5 miles down a creek with a current for 2 hours. Since this is faster, it means that she swam with the current. Her total speed would be (x + y) mph

Distance = speed × time

Therefore,

5 = 2(x + y)

dividing both sides by 2, it becomes

2.5 = x + y- - - - - - -1

It takes her 4 hours to swim the same 5 miles back to her original destination against the

same current. It means that her total speed was (x - y) mph

Distance covered would be

5 = 4(x - y)

Dividing both sides by 4, it becomes

1.25 = x - y- - - - - - - 2

Adding equation 1 to equation 2, it becomes

3.75 = 2x

x = 3.75/2

x = 1.875

Substituting x = 1.875 into equation 1, it becomes

2.5 = 1.875 + y

y = 2.5 - 1.875

y = 0.625