Results 1 to 5 of 5

Math Help - anybody help me arithmetic problems

  1. #1
    Member
    Joined
    Jan 2008
    Posts
    173

    anybody help me arithmetic problems

    1) If there are 1.15 land miles in a nautical mile, how many land miles are there in 10 nautical miles?


    2) A trip takes 5 hours in a car moving 40 miles per hour. How long would the trip take in a train moving at 100 miles per hour?



    3) It takes Bill 4 hours to do a job. It takes Jane 2 hours to do the same job. How many such jobs could they do together in 4 hours?


    please give me solutions

    Thank you

    Sri
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Newbie
    Joined
    Mar 2008
    From
    Germany
    Posts
    4
    Appendage?
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Member SengNee's Avatar
    Joined
    Jan 2008
    From
    Pangkor Island, Perak, Malaysia.
    Posts
    155
    Quote Originally Posted by sri340 View Post
    1) If there are 1.15 land miles in a nautical mile, how many land miles are there in 10 nautical miles?


    2) A trip takes 5 hours in a car moving 40 miles per hour. How long would the trip take in a train moving at 100 miles per hour?



    3) It takes Bill 4 hours to do a job. It takes Jane 2 hours to do the same job. How many such jobs could they do together in 4 hours?


    please give me solutions

    Thank you

    Sri
    1)

    T_{10}=a+9d=(1.15)+9(1.15)=11.5 land miles


    2)

    v=\frac{s}{t}
    s=vt
    t=\frac{s}{v}

    Distance travelled =40\times 5=200miles

    t=\frac{200}{100}=2hours


    3)

    Bill takes 4 hours to do 1 job.
    Jane takes 2 hours to do 1 job.
    Therefore, Jane takes 4 hours to do 2 jobs.

    They takes 4 hours to do 3 jobs.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Junior Member
    Joined
    Mar 2008
    Posts
    41
    a simpler way of looking at #1 is


    1mile 10 miles
    _____ x _______
    1.15 X



    (10)(1.15)
    _________ = 11.5
    1
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Senior Member
    Joined
    Feb 2008
    From
    Berkeley, Illinois
    Posts
    364
    It's a proportion problem:

    \frac{1.15lm}{1nm} = \frac{xlm}{10nm}  \rightarrow lm = land miles and nm = nautical miles

    Use cross multiplication to get:

    1.15 * 10 = x
    x = 11.5

    For future proportions, feel free to check your answer or future answers like it here:

    Proportions
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Arithmetic series..... other problems..
    Posted in the Math Topics Forum
    Replies: 2
    Last Post: May 19th 2010, 09:53 PM
  2. Arithmetic series..... Log.. other problems..
    Posted in the Algebra Forum
    Replies: 2
    Last Post: May 19th 2010, 10:10 AM
  3. Arithmetic Progression or Arithmetic Series Problem
    Posted in the Math Topics Forum
    Replies: 1
    Last Post: October 8th 2009, 01:36 AM
  4. arithmetic
    Posted in the Number Theory Forum
    Replies: 1
    Last Post: April 26th 2009, 11:24 AM
  5. arithmetic in Z/nZ
    Posted in the Number Theory Forum
    Replies: 1
    Last Post: January 12th 2009, 06:01 PM

Search Tags


/mathhelpforum @mathhelpforum