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-   -   Average speed 2 (https://www.askmehelpdesk.com/showthread.php?t=513092)

  • Oct 3, 2010, 06:12 AM
    Eloisea1
    Average speed 2
    Ali walked 1km in 12 minuets. He stopped for 10 minuets and then walked a further 3km in 38 minuets. Calculate his average speed in km/h. I understand that average speed = total distance dive total time , so should I add the time ali stopped as well? Can anyone help please? Thanks.
  • Oct 3, 2010, 06:25 AM
    Unknown008

    Yes, you would add the time he stopped too. What counts, is the time he departed and the time he arrived.

    Can you give what you get? :)
  • Oct 3, 2010, 06:32 AM
    Eloisea1
    Comment on Unknown008's post
    So he walked 4km in 60mins so it is... 4 divide 60? Which is 0.06?
  • Oct 3, 2010, 06:40 AM
    Unknown008

    Hm... not quite.

    What you got is the speed in km/min

    Convert into hours as you were asked now.

    In 1 minute, he covers 0.06666 km
    In 60 minutes, he covers 0.06666 x 60 = 4 km/hr
  • Oct 3, 2010, 06:56 AM
    Eloisea1
    Comment on Unknown008's post
    3.9996? I am confused :S
  • Oct 3, 2010, 07:03 AM
    Unknown008

    Right, but you didn't take all the numbers.

    The actual distance he covers in 1 minute is

    Multiply that by 60, to get:

  • Oct 3, 2010, 07:08 AM
    Eloisea1
    Comment on Unknown008's post
    So is it 4km/h?
  • Oct 3, 2010, 07:10 AM
    Unknown008

    Yes it is :)
  • Oct 3, 2010, 07:24 AM
    Eloisea1
    Comment on Unknown008's post
    Thank you , and possibly 1 last question? I have posted it on average speed 3 , and have used what you taught me , darren ran a 200m race in 24 seconds what was his average speed for the race in m/s? Is it 8.3m/s and his av sp in km/h 20.88 km/h
  • Oct 3, 2010, 07:52 AM
    Eloisea1
    Average Speed 3
    a. Darren ran a 200m race in 24 seconds. What was his average speed for the race in m/s. Is it 8.3? And also I have to find his average speed in km/h. can anyone help with both questions please?
  • Oct 3, 2010, 08:42 AM
    Unknown008

    i have posted it on average speed 3 , and have used what you taught me , darren ran a 200m race in 24 seconds what was his average speed for the race in m/s? Is it 8.3m/s and his av sp in km/h 20.88 km/h

    1. Right
    2. Not quite...

    200 m = 0.2 km
    24 s =

    So, speed =

    Or from you initial speed:


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