keystone dec 2011

During the year Keystone manufactured an item of plant for its own use. The direct materials and labour were
$3 million and $4 million respectively. Production overheads are 75% of direct labour cost and Keystone
determines the final selling price for goods by adding a mark-up on total cost of 40%. These manufacturing costs
are included in the relevant expense items in the trial balance. The plant was completed and put into immediate
use on 1 April 2011

The plant in the trial balance will be depreciated by $6 million ((44,500
– 14,500) x 20%) for the year and have a carrying amount at 30 September 2011 of $24 million

please why 10 000 of the production of plant are reduce from the cost of plant in the sofp?
44 500- 14500 -10 000. but the answer ignored those $10 000

thx