Question

A river's current is 4mph. A boat travels 48 miles downstream in the same time it travels 24 miles upstream. Find the speed of the boat.

A) What does the variable stand for?

x stands for the speed of the boat.

B) Write the equation.

24/x - 4 = 48/x + 4

C) Solve.

24/x - 4 = 48/x + 4

24(x + 4) = 48(x - 4)

24x + 96 = 48x - 192

288/24 = 24x/24

mph 12 = x

D) Write the answer in a complete sentence.

The speed of the boat will be 12 miles per hour.

Is this correct?

Answer 1

Yes, it is correct. The upstream speed relative to land (8 mph) is half the downstream speed (16 mph), as required.

Answer 2

Thanks