Assume a Nike outlet store began in august 20X0 with 40 pairsof running shoes that cost the store $40 each. The sale price of the shoes was $70. During august the store completed these inventory transactions: (for the three sets of #'s below, the first column is the units, the second is unit cost, and the last is unit sale price)

                                                                           Units   Unit Cost     Unit Sale Price
aug. 3Sale.....                                                       16        $40                  $70
8Purchase.....                                                       80        $41
11Sale.....                                                             24        $40                  $70
19Sale.....                                                              9          $41                  $72
24Sale.....                                                             30         $41                  $72
30Purchase.....                                                     18         $42

I've been stuck on this two part problem for two days and thebook says to:

a) determine the store's cost of goods sold for august. Also compute the GP for august. When I did it I kept getting$1,456 but the answer key shows $2,409.

b) what is the cost of the stores august 31 inventory ofrunning shoes? when I did this one I got $1,484 but the answer key shows $2,437.