CPA-05404
Basically the problem gives us this information:
Unrecognized prior service cost $375,000
Unrecognized net gain 50,000
Unrecognized transition obligation 135,000
Zen has an effective tax rate of 40%.  What amount would Zen report in accumulated other comprehensive income related to its pensions plan on its December 31, 20x7 balance sheet?
The answer was 375,000 - 50,000 + 135,000 = 460,000 x 60% = 276,000.

I undestand this answer but on the next question, CPA-05406, it gives us this information:
Service cost 300,000
Interest cost 175,000
Expected return on plan assets (100,000)
Amortization of prior service cost 40,000
Amortization of net gain (15,000)
    Net periodic pension cost  400,000
Amerigenie has an overfunded pension plan.  The company's affective tax rate is 30%.  How will the amortization of the net gain affect the 20x9 balance sheet?

One of the answer choices was 15,000 decrease in accumulated other comprehensive income.  Now according to Becker's explanation,this choice is incorrect because 15,000 was not net of tax (it should've been 10,500 decrease in OCI). 

My question is...  assuming the amount was correct and the option was 10,500 decrease in OCI.... why is that true?  In the very first CPA question that I posted above, any unamortized gain was subtracted from OCI.  If we amortized it and removed it from OCI, wouldn't that have INCREASED OCI (we subtracted it when calculating OCI in the first problem)?