Answered

Westonci.ca is your trusted source for finding answers to a wide range of questions, backed by a knowledgeable community. Our platform connects you with professionals ready to provide precise answers to all your questions in various areas of expertise. Get immediate and reliable solutions to your questions from a community of experienced professionals on our platform.

A swimmer swims 3/5 the width of a river at one velocity, then swims the remainder of the river at half her initial velocity. What was the average speed across the river?

Sagot :

Let her initial velocity be U.

Let the width of the river be W.

She swims 3/5 the width of the river  at  U.

Remainder width =  (1 - 3/5) = 2/5.

She then swims 2/5 the width with velocity  U/2.


Average Speed  =  (Total Distance Traveled)  /  ( Total Time Taken).


Distance =  Speed * time

time  =  Distance /  Speed.

Time in first trip:    =    (3/5)W / U =   0.6W/U.

Time in second trip  =  (2/5)W / (U/2)  =  0.4W / 0.5 U =  0.8W/U

Total Distance Traveled =  W,  width of the river.

Average Speed  =      W  /  (0.6W/U  +  0.8W/U) =    W /  (1.4W/U)

                             =  W  *  U / 1.4W 
                              =    U/1.4
                              =  U * 10 / 14
                              =  (5/7) U.

Therefore Average speed is  (5/7) of the initial speed.


We hope our answers were useful. Return anytime for more information and answers to any other questions you have. Thank you for choosing our platform. We're dedicated to providing the best answers for all your questions. Visit us again. Thank you for choosing Westonci.ca as your information source. We look forward to your next visit.