Consolidated retained earnings

BPP revision kit: page 31: Q105

– P acquired S on 1st April 2008
– Consolidated RE to be calculated for the year ended 30 September 2008.
– At acquisition date fair value of a depreciable non-current asset was 2m in excess of its carrying amount. remaining life at date of acquisition is 5 years (straight-line method).

My question is:
When calculating the consolidated retained earnings i get 18,000 for fair value adjustment of this asset. ((2m minus (2m/5 multiplied by 0.5)). However in the answer the fair value adjustment shows only 200, which is the depreciated amount before acquisition.
In ur notes chapter7: Q11 you took the fair value remaining after depreciation, but in this answer they have used the depreciation amount itself. Please explain.