How is the $10,000 cost basis determined? I keep getting $15,000 for the determined loss and then (1/3) of that, which is $5,000 loss that cannot be recognized, but that's not the correct answer. What am I doing wrong?

Broward Corp. owns 1,500 shares of Silver Fox Corporation common stock. Broward Corp. purchased the 1,500 shares on April 17, 2011, for $20,000. On December 8, 2016, Broward sells 750 shares for $5,000. On January 2, 2017, Broward Corp. buys 250 shares of Silver Fox Corporation common stock for $1,750 and 50 shares of Silver Fox Corporation preferred stock for $1,000. The preferred stock is nonvoting, nonconvertible.

a. What is Browards realized and recognized loss on the December 8 sale of stock?