Question

A whale swimming against an ocean current traveled 140 mi in 7 h. Swimming in the opposite direction, with the current, the whale was able to travel the same distance in 3.5 h. Find the speed of the whale in calm water and the rate of the ocean current.

Answer 1

The whale exists swimming at 30 mph in calm water and the current exists flowing at 10 mph.

How to estimate the speed of the whale in calm water and the rate of the ocean current?

Let x be the speed of a whale in calm water

and y be the speed of the current

In 7 hours the whale swims against the current and travels 140 miles:

7(x - y) = 140

x - y = 140/7

x - y = 20 ...........(1)

In 3.5 hours the whale swims the same distance with the current:

3.5(x + y) = 140

x + y = 140/3.5

x + y = 40 ...........(2)

Adding (1) and (2), we get the value of x:

x - y = 20  + ...........(1)

x + y = 40 ...........(2)

-----------------

2x = 60

x = 60/2

x = 30

Using this value for "x" in either (1) or (2) we can solve for "y":

x - y = 20 ...........(1)

substitute for "x"

30 - y = 20

10 = y

Therefore, the whale exists swimming at 30 mph in calm water and the current exists flowing at 10 mph.

To learn more about the values of x and y refer to:

https://brainly.com/question/1066617

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