Have a doubt in this pls help :(

ali (Student CA CPT ) (130 Points)

06 March 2014  
i have attached a pic of the question kindly any one tel me how to find the answer for 7(5) and 7(6) value of issue and value of closing stock for the month of december using simple average method.. i tried solving many times but did not get the answer in text book answer for the above questions is 7(5) 1750(closing stock) 7(6) 56250(issues )