please help me how to find red box part only

please show math work too. thank you.

Ivanhoe Publishers sells textbooks to universities across Canada. On July 10, 2021, Ivanhoe entered into a contract with Hinton University to supply 330 accounting textbooks at a price of $110 per book to be paid on September 25, 2021. The books cost Ivanhoe $89 each. Ivanhoe's return policy states that any unsold books can be returned within 90 days of delivery. The books were delivered on August 25, 2021. Ivanhoe estimates returns at 10% of sales. Hinton returns 11 books on September 15, 2021, and 22 books on September 30, 2021. * Your answer is incorrect. Determine the transaction price. Transaction price $ 36300 Date 36300 Account Titles and Explanation Accounts Receivable August 25, 2021 Refund Liability Sales (To record sales on account.) 2931 August 25, 2021 Inventory Returns 29370 Cost of Goods Sold Merchandise Inventory (To record cost of goods sold.) 1210 September 15, 2021 Refund Llability Accounts Receivable (To record credit for goods returned.) September 15, 2021 Merchandise Inventory 989 Inventory Returns (To record credit for goods returned.) Cash September 25, 2021 35090 Merchandise Inventory (To record cost of goods sold.) Refund Liability 1210 September 15, 2021 Accounts Receivable (To record credit for goods returned.) 989 September 15, 2021 Merchandise Inventory Inventory Returns (To record credit for goods returned.) 35090 September 25, 2021 Cash Accounts Receivable (Collection on account.) Refund Liability 2376 September 30, 2021 Cash (To record cash refund for goods returned.) Merchandise Inventory September 30, 2021 1958 Inventory Returns (To record cost of goods returned.)