Belle Epoch Fashion began August with 150 pairs of Traveler slacks. Each pair cost $25. Relevant information is listed as follows:

If Belle Epoch Fashion uses the periodic inventory system and the FIFO inventory cost flow assumption, what is its gross profit for the month?

I know that cost of good sold= 150x25 +150x29 + 150x33. Please explain to me how to get that 150x33.

Purchase Sale Purchase Sale August 9 August 13 August 22 August 29 150 units at $29 per unit 200 units at $55 per unit 200 units at $33 per unit 250 units at $55 per unit