Am ventilating a 1800 square foot attic. How many square inches of exhaust should there be? I've been given several answers, which is the correct answer? 2718,1728,211,864.

The exhaust venting is proportional to the inlet soffet vents. Attic Vent Calculation

If they aren't already there, locate your soffit vents as close to the fascia and roof deck as possible. Use continuous strip vents as opposed to the smaller, circular port vents.

Ok, I quoted different answers from above and I still was not given the right answer. So, help me out. Which is the right answer? 2718, 1728,211,864 of square inches of exhaust ventillation needed for an 1800 sq ft attic?

Using the formula I gave in post 2 you need 6 s/f of both soffit and vent. In s/ inches that is 864