I have a number of fish tanks in my inventory," he explains. "At first, I bought 50 of them at a wholesale cost of $17 each. At the beginning of the month, I still had 36 left. So I bought 14 more, but now the same fish tank costs me $22. I've sold half of the fish tanks I had in stock since then, so I have 25 left."

Calculate these using the LIFO, FIFO, and weighted average method.