motion problem

posted by .

A man rowed 30km downstream. it took him 2hrs more time in going back than in going downstream. if the current is 2kph, what is his speed in still water?

(with solution pls... tnx)

  • motion problem -

    since time = distance/speed, if his speed is s, then

    30/(s-2) = 2 + 30/(s+2)
    s = 8

    check:
    downstream: 30/10 = 3
    upstream: 30/6 = 5

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Help...More Math Help!!!...Please!

    A kayaker paddled 2 hours with a 6 mph current in a river. The return trip against the same current took 3 hours. Find the speed the kayaker would make in still water. The speed is 6 mph slower going upstream and 6 mph faster going …
  2. algebra

    HOW DO SOLVE A BOAT TRAVELED 336 MILES DOWNSTREAM AND BACK. THE TRIP DOWNSTREAM TOOK 12 HOURS. THE TRIP BACK TOOK 14 HOURS. WHAT IS THE SPEED OF THE BOAT IN STILL WATER?
  3. Algebra

    What system of equations do I use to solve the following question?
  4. MATH

    1. A boat traveled 210 miles downstream and back. The trip downstream took 10 hours, the trip back took 70 hours. What is the speed of the boat in still water?
  5. math

    A boat traveled 210 miles downstream and back. The trip downstream took 10 hours. The trip back took 70 hours. What is the speed of the boat in still water. What is the speed of the current?
  6. math

    Seven people rowed 12 miles downstream with the current in 1.5hrs. Coming back upstream against the current covered the same distance but took 4 hours. Find the people rowing rate in the still water and the rate of the current
  7. linear equations in two variable

    A person going at a rate of 5 km/hr in still water,takes thrice as much time in going 40km upstream as in going downstream. Find the speed of the stream.
  8. algebra 1

    a bout travels 280 miles downstream and back. The trip downstream took seven hours. The trip back took 14 hours. The speed of the boat in still water and the speed of the current
  9. Algebra

    A boat traveled 180 miles downstream and back. The trip downstream took 10 hours. The trip back took 30 hours. Find the speed of the boat in still water and the speed of the current. Solve each system using any method
  10. Rate Problem / College Algebra

    Kim rowed 45mph Upstream. The next day she rowed the same distance Downstream taking her 4hrs less. If she can row 7mph in still water, find the speed of the current river. **Note: this question does not state how much time she's been …

More Similar Questions