good will

that past paper didn’t require calculate good will, the practice kit required and information which was past paper is the same as practice kit, help me please!
thanks a lot

thank you for your asking, that question is ACCA f7 past paper June 2011, namely Prodigal.
On 1 October 2000 Prodigal purchased 75% of the equity shares in Sentinel. the acquisition was through a share exchange of two shares in Prodigal for every three shares in Sentinel. the stock market price of Prodigal’s shares at 1 October 2000 was 4 per share.
the following information for the equity of the companies at 1 April 2000(ie before the share exchange took place) is available:
Prodigal Sentinel ($000)
equity share of $1 each 250,000 160,000
share premium 100,000 nil
revaluation reserve(land) 8,400 nil
other equity reserve 3,200 2,200
retained earnings 90,000 125,000
the answer shown that when calculating the good will , the net assets on DOA : sentinel’s share 160,000 +equity reserve 2200 +retained earnings 125,000 which are shown on 1 April 2000’s statement, my question is that why it didn’t add 66600×6/12? because the acquisition day is 1October 2000. hopefully I described clearly.
many thanks

Sorry for response too late, the BPP answer is that:
consideration(((160,000×75%)x2/3)x$4) 320,000
Fair value of non-controlling interest 100,000
fair value of net asset:
shares 160,000
other equity reserve 2,200
retained earnings 125,000
good will 132,800
I am very confused
many thanks

thank you Sir