Dottie will probably chime in here in a bit with your answer re the FSIQ, but I can help with the GAIs in the meantime since the change in the PSI won't impact calculating the GAI. GAI looks only at VCI and PRI.

For twin#1, the GAI would be 139 and for twin#2, the GAI would be 136. The WISC technical report #4, which is what one uses to calculate the GAI, is available online: http://www.ksde.org/Portals/0/Special%20Education%20Services/gifted/WISCIVTechReport4.pdf

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