Why is the manometer problem solution calculated incorrectly?

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The discussion centers on a miscalculation in the manometer problem involving two connected pipes. The user calculated the pressure difference PB - PA as 3.33 kPa, but the expected answer was -3.33 kPa. The confusion arose because the problem specifically asked for PA - PB, leading to the sign error in the final result. Clarification was provided that reversing the order of subtraction changes the sign of the answer. Understanding the correct interpretation of pressure differences is crucial in solving such problems accurately.
aaronfue
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Homework Statement



Two pipes are connected by a manometer shown in the figure.

Homework Equations



FR = \gamma*hc*A

yR = yc + \frac{I_xc}{y_c*A}

The Attempt at a Solution



PB - PA = \gammawater*1.1m - \gammaFluid*0.6m + \gammawater*0.8m = 3.33 kPa

I checked my answer and it was all okay except the answer was supposed to be -3.33 kPa. Can someone brief me on why that is?
 

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The problem asked for PA-PB, and you calculated PB-PA.
 
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