Answer: her swimming speed = 1.875 mph
Speed of current = 0.625 mph
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