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So I'm new to the dimensional analysis world and I'm little confused and the answers I'm getting are not convincing :(

if the concentration of hemoglobin in a 5ml sample of blood is 34 g/dL. and red blood cells are 31.45 hemoglobin, what is the mass of red blood cells in the sample?

So.. any thoughts on how to do it?

Thank you so much

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It doesn't seem like you need the 31.45 hemoglobin number (which is good because no units are given:

5ml * 34g rbc /dL * 1 dL/ 100 ml = 1.7 g rbc

would fall out from unit analysis

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Thank you!! hemoglobin's unit is percentage. 31.45% so should i just multiply your number it with that? – user6058 Mar 17 '14 at 20:07
Shigeta's equation should have used "hgb" instead of "rbc". To turn 1.7g hgb into rbc, you multiply it by the .3145 hgb/rbc value. Note the dimensional units work out. – mgkrebbs Mar 17 '14 at 20:13
THANK YOU THANK YOU THANK YOU !! I GOT IT!! – user6058 Mar 17 '14 at 23:41
@user6058 Please accept the answer if you have got it :P – biogirl Apr 14 '14 at 16:45

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