Thread: Find the Speed

During the first part of a trip, a canoeist travels 37 miles at a certain speed. The canoeist travels 7 miles on the second part or the trip at a speed 5 mph slower. The total time for the trip is 4 hours. What is the speed on each part of the trip?

Hello, magentarita!

During the first part of a trip, a canoeist travels 37 miles at a certain speed.
The canoeist travels 7 miles on the second part or the trip at a speed 5 mph slower.
The total time for the trip is 4 hours.
What is the speed on each part of the trip?

We will use: .

Let = speed on the first part.
Then = speed on the second part.

He went 37 miles at mph.
. . This took: . hours.

He went 7 miles at mph.
. . This took: . hours.

His total time was 4 hours: .

Now solve for . . .


Warning: We get a quadratic that doesn't factor.
. . . . . . .Use the Quadratic Formula and approximate the answer.
.

Originally Posted by Soroban

Hello, magentarita!

We will use: .

Let = speed on the first part.
Then = speed on the second part.

He went 37 miles at mph.
. . This took: . hours.

He went 7 miles at mph.
. . This took: . hours.

His total time was 4 hours: .

Now solve for . . .


Warning: We get a quadratic that doesn't factor.
. . . . . . .Use the Quadratic Formula and approximate the answer.
.

Thanks for your reply and the tip at the end.