Don Williams uses his small motorboat to go 5 miles upstream to his favorite fishing spot. Against the current, the trip takes 1

Question

Dmitry_Shevchenko [17]

3 years ago

12

Don 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?

Mathematics

2 answers:

Alex17521 [72] · Answer 1 · 2022-07-23T05:24:43+03:00

Alex17521 [72]3 years ago

6 0

12 MPH GOING UP STREAM.

castortr0y [4] · Answer 2 · 2022-07-23T06:40:39+03:00

Suppose x is the rate at which the boat travels at still water.
let y be rate in moving water
up stream is x-y
down stream is x+y
the 1/3(x-y)=5
1/5(x+y)=5
solve the system
x-y=15
x+y=25
add the equation to cancel y
we get 2x=40
x=20
therefore the boat is moving at rate of 20 miles for hour in still water