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    Hi I have this equation, c= (10000qp/q) + cf

    Cf is the concentration of co2 in the incoming air which is 3 in a room

    qp is the average production of co2 by a person in a room which is 4.7 x 10 ^-6 m^3 s^-1

    C is the concentration of co2 in the room which must not exceed 10

    q is the room volume at 340 ^m3 for 14 people

    The question is if 21 people are in the room, to what value must q be increased to.

    thank you
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    Which of the letters represents the No of people?
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    Hi,

    sorry, the full formula is,

    it is actually c = (10000qpN3600)/q + cf

    3600 is the time in seconds at which a room of 340^m3 recives a change of air.

    N = the number of people

    thanx
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    (Original post by Samh)
    Hi,

    sorry, the full formula is,

    it is actually c = (10000qpN3600)/q + cf

    3600 is the time in seconds at which a room of 340^m3 recives a change of air.

    N = the number of people

    thanx
    I worked the answer out as 507.6 m^3 for new value of q I dont know if it is right or not.
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    You know you really should do your own homework

    OK replacing the algebra for known values.

    c=((10000*3600*4.7*10^-6*N)/340)+3
    = ((169.2*N)/340)+3

    for 14 people c will equal 9.96

    for 21 people to get a value of C=10 and assuming that cf stays about the same

    10=(169.2*21)/q+3
    10-3=3553.2/q
    7q=3553.2
    q=507.6m^3

    This would best be rounded up to 510m^3 to keep C below 10.
 
 
 
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