Results 1 to 2 of 2

Math Help - Work Problem

  1. #1
    Newbie
    Joined
    Dec 2009
    Posts
    1

    Work Problem

    I need help with this problem. I have no idea how to go about it! Why can't math just use numbers and not words?!

    "Fern can fly her plane 240 miles against the wind in the same time it takes her to fly 360 miles with the wind. The speed of the plane in still air is 30 mph more than four times the speed of the wind. Find the speed of the plane in still air."


    Fff, I meant "word problem," not "work."
    Last edited by anotherMelissa; December 3rd 2009 at 09:26 AM. Reason: Misuse of words!
    Follow Math Help Forum on Facebook and Google+

  2. #2
    A riddle wrapped in an enigma
    masters's Avatar
    Joined
    Jan 2008
    From
    Big Stone Gap, Virginia
    Posts
    2,551
    Thanks
    12
    Awards
    1
    Quote Originally Posted by anotherMelissa View Post
    I need help with this problem. I have no idea how to go about it! Why can't math just use numbers and not words?!

    "Fern can fly her plane 240 miles against the wind in the same time it takes her to fly 360 miles with the wind. The speed of the plane in still air is 30 mph more than four times the speed of the wind. Find the speed of the plane in still air."


    Fff, I meant "word problem," not "work."
    Hi anotherMelissa,

    Seems that lots of students don't like word problems. I believe it has to do with their lack of experience with them. You have to parse the words, extract the data, make some sense about how to arrange the data, create an equation or equations of some kind, and then solve the darn thing. Seems like a "work" problem to me.

    Ok, so here goes.

    Let w = speed of the wind

    Let 4w + 30 = speed of the plane in still air

    Distance = rate X time

    Time is constant. Time = Distance / rate

    Let D1 = 240 (distance traveled against wind)
    Let D2 = 360 (distance traveled with wind)

    Let r1 = (4w+30)-w (rate against the wind)
    Let r2 = (4w+30)+w (rate with the wind)

    \frac{D_1}{r_1}=\frac{D_2}{r_2}

    \frac{240}{4w+30-w}=\frac{360}{4w+30+w}

    Solve for w (speed of wind)

    Solve for 4w + 30 (speed of plane in still air)
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. work problem
    Posted in the Calculus Forum
    Replies: 2
    Last Post: December 18th 2010, 12:53 PM
  2. Work problem
    Posted in the Calculus Forum
    Replies: 0
    Last Post: March 1st 2010, 10:06 AM
  3. Work Problem
    Posted in the Algebra Forum
    Replies: 2
    Last Post: October 14th 2008, 05:56 AM
  4. Help with work problem
    Posted in the Calculus Forum
    Replies: 1
    Last Post: June 4th 2008, 12:18 PM
  5. work problem
    Posted in the Math Topics Forum
    Replies: 3
    Last Post: February 11th 2008, 10:26 AM

Search Tags


/mathhelpforum @mathhelpforum