2 questions on minority interest under Acquisition method

1, Equity under this method is higher as you add the non-controlling interest part, that´s clear but sometimes I see that only equity of minority interest is added and sometimes also its portion of sub´s retained earnings? Which approach is correct - with or without retained earnings?

2, Sometimes the calculation of non-controlling minority interest portion is based on book value from balance sheet and sometimes I have seen in mocks that it was calculated based on the price ie when you paid 100 for 50%, the non-controlling minority interest portion of equity added was the other 100. Again, which approach is correct?

Thanks a lot for your help!

Anyone can help here??