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    A man cycles to work with the wind at 8.0 m/s and returns home against the wind at 4 m/s. What is his average speed? (hint:It is not 6 m/s)

    I'm probably missing something obvious ?
    thanks
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    are you sure it's speed and not velocity?
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    (Original post by cardine92)
    are you sure it's speed and not velocity?
    100% lol
    thats why im confused. any ideas ?
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    5.3 ms-1
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    want to know why or want to work it out your self?
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    (Original post by Katermerang)
    want to know why or want to work it out your self?
    whyy please?
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    Ok well lets write down the basics first:

    Speed= Distance/time

    Distance = d
    Time to work=T1
    Time back = T2

    so you can write two equations form this data to work out the two individual speeds (to work and back)

    8= d/T1 and 4= d/T2

    Now Average speed = total distance/total time

    so a rearrangement of the top equations gives:

    Average speed = [2d] / [ (d/8) + (d/4)]

    The "d"s cancel out leaving you with (16/3) or 5.3ms-1
 
 
 
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