Results 1 to 5 of 5

Math Help - Need urgent help with Related Rates

  1. #1
    Newbie
    Joined
    May 2009
    Posts
    19

    Smile Need urgent help with Related Rates

    Could anyone help me by solving this step by step so I can see what you did there?
    Thank you so much in advance.


    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor Calculus26's Avatar
    Joined
    Mar 2009
    From
    Florida
    Posts
    1,271
    R = 110q - q^2/200

    dq/dt = 55 the rate production is increasing and q = 400

    Now we differentiate with respect to time -- note d(q^2)/dt = 2q dq/dt


    dR/dt = 110dq/dt -q/100 dq/dt

    dR/dt = 110(55)-(400/100)(55)

    dR/dt = 6050 - 220 = 5830dollars/day
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    May 2009
    Posts
    19

    Smile

    Quote Originally Posted by Calculus26 View Post
    R = 110q - q^2/200

    dq/dt = 55 the rate production is increasing and q = 400

    Now we differentiate with respect to time -- note d(q^2)/dt = 2q dq/dt


    dR/dt = 110dq/dt -q/100 dq/dt

    dR/dt = 110(55)-(400/100)(55)

    dR/dt = 6050 - 220 = 5830dollars/day
    Thank you so much Calculus26. I'm just uncertain about the last answer, a friend of mine told it can't be $5830. He said that I might wanna try plugging in the derivative, but I 'm not sure what I'm getting wrong here.
    Any ideas?
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor Calculus26's Avatar
    Joined
    Mar 2009
    From
    Florida
    Posts
    1,271
    I am going to stand by answer--what does your friend suggest the answer

    should be? What do you mean exactly by plugging in the derivative?
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Newbie
    Joined
    May 2009
    Posts
    19

    Smile

    Quote Originally Posted by Calculus26 View Post
    I am going to stand by answer--what does your friend suggest the answer

    should be? What do you mean exactly by plugging in the derivative?
    Your answer was definitely correct. My buddy was mistaken. Thank you again, Calculus26!
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. rates and related rates
    Posted in the Calculus Forum
    Replies: 2
    Last Post: October 29th 2007, 09:51 PM
  2. Urgent help on related rates:
    Posted in the Calculus Forum
    Replies: 1
    Last Post: March 18th 2007, 07:41 AM
  3. Related Rates, urgent
    Posted in the Calculus Forum
    Replies: 2
    Last Post: February 27th 2007, 07:43 AM
  4. Related rates: urgent
    Posted in the Calculus Forum
    Replies: 1
    Last Post: January 6th 2007, 09:25 PM
  5. Related rates: urgent
    Posted in the Calculus Forum
    Replies: 2
    Last Post: January 6th 2007, 05:00 PM

Search Tags


/mathhelpforum @mathhelpforum