There's some intelligence difference between population groups, let's say Group A and Group B. Lets say that Group B is measured to be on average 5p more intell

There's some intelligence difference between population groups, let's say Group A and Group B. Lets say that Group B is measured to be on average 5p more intelligent based on whatever arbitrary measure we took. The debate here is about whether we should try to change the environment in such way that Group A and Group B would be more similar. We know that Group A in general has poorer environment however there's an argument that improving those conditions won't bring Group A to Group B level anyway since it's mostly genetical. Progressives want to change the environment, conservatives think it's a futile effort. How would you determine in the following scenario whether levelling the playing field would cause the averages to be the same? Would 70-80% imply that, yes, it's likely and under what circumstances? If the variance for a single person's measurement could be around 40p, then if genetics is causing 75% of it, then it would be responsible for 30p of that and environment 10p, then can we deduce that Group A given similar environment would actually be 5p higher in intelligence? In this case while genetics describe 75% of the variance, environment is still enough to make naturally more gifted group less successful. So without knowing the other variables the 70-80% is still not meaningful.