It has been a looooooong time since I took stats so hopefully someone will correct me if needed but I believe it should apply to any standard bell curve with an SD of 15.

So using the same chart you can figure out that 1/x people have a GAI over a if you use their GAI for a and 1/y people have a FSIQ over b where b==FSIQ. For kids with very different GAI and FSIQ (a & b) you could have very different x and y values.

too slow smile

Last edited by chay; 05/04/16 09:01 AM.