Goodwill

don’t get wrong concept. You just need little understanding here, let me clear, as u know in goodwill calculation pre-acquisition retained earning will be added but do u have any idea what is pre-acquisition retained earning ? pre-acquisition retained is on the date when parent acquires subsidiary or before that period.
in this question u need to calculate pre-acquisition retained earning and u must remember that how closing retained earning come on SFP.
Closing retained earning:
opening retained earning xxx
add/less profit/loss for the period
less dividend paid
then comes closing retained earning
now just go reverse to find out opening retained earning which is pre-acquisition retained earning. loss of 3000 for the period was deducted from opening retained earning then closing retained earning became 6300 , now just add loss of 3000 into closing retained earning of 6300 then u will get pre-acquisition retained earning of 9300.

Thanks. hope it is clear to u now.

any way but what this means is that the first 3000 profit made was used to cancel out the loss at the date of acquision and then 6300 is reported as profit for the period.
so
Retain Earning at the Beging : (3000)
Profit for the year :+ 9300
profit at the end : := 6300