NCEES 2001 Exam - #507

[BuffaloWings]

Could anyone provide a better solution and explanation to this problem than what they provide in the book?

I got the wrong answer because I multiplied the mass flow rate of the air stream by the inlet & outlet humidity ratios and kept the mass flow rate of water stream stay constant.
 

I guess I should have not multiplied the air flow rates by the humidity ratios and instead removed the mass rate of evaporation from the mass flow rate of water. 

 

[MikeGlass1969]

Do you have the answer or the solution...  I fell smack dad in the middle of two answers.  Which means I probably did the whole thing wrong.

Nevermind...i have it

 

[BuffaloWings]

Answer is B. I can post their solution if needed. 

 

[MikeGlass1969]

I figured their method out last night.  I just wanted to put it in MathCad.