There’s an error with your calculation.
Total pages/s= 3*8/236.35ms.
In each multiframe, you have 8 paging blocks, not 4*8. You should not multiply 8 by 4(the MFRMS), otherwise, the denominator of ur equation should also be multiplied by 4.
The MFRMS indicates the repetition period(in terms of number of multiframes) for each paging group. Thus, it should only be used to determine the number of paging groups.