Why isn't this right? Finding the Va-Vb, kirchofs rule

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The discussion revolves around calculating the potential difference Va - Vb in a circuit with specified resistances and battery emfs. The user correctly calculated the current through each battery but reported an incorrect potential difference of 3.34 V. Participants in the forum are helping to identify the error in the user's calculations. The focus is on applying Kirchhoff's rules and understanding the relationships between current and voltage in the circuit. Clarifying the calculations and reviewing Kirchhoff's laws are essential for resolving the discrepancy.
mr_coffee
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Hello everyone, this seems easy enough...but i missed it!
Here is the drawing and here is my work:
http://img203.imageshack.us/img203/3928/lastscan7qe.jpg
In Figure 27-40, the resistances are R1 = 1 , R2 = 2.2 , and the ideal batteries have emfs E1 = 2.0 V, and E2 = 3 = 3 V.
http://www.webassign.net/hrw/hrw7_27-40.gifFig. 27-40

(a) What is the current through each battery? (Take upward to be positive.)
Battery 1: -.328125
Battery 2: .15625
Battery 3: .171875
I found all these and got them right.

What is the potential difference Va - Vb?
3.34 <-- wrong

How did i mess up ? Thanks
 
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N/m i got it!
 

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