what is 3d rpk and what is the cost difference?

Do you mean 3D RPX? If so, there is a difference. Simple 3D of course means that you get the 3D glasses to see the movie in 3D. But RPX is different. RPX comes in both 2D and 3D formats, but what makes it cool is that the seats vibrate with the movie, commensurate of their name: "Buttkicker" seats. Even so, if you want 3D, you will pay up to $14.85 (Less for Senior, Child, or any other discounts, such as for students or military). Adding RPX to that will raise that to a maximum of $16.78, which translates to approximately $2 worth of upgrades. Hopefully this helps. 😁 Source: Fandango App for Android

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