Carson Bike Shop started operations in 2016. During its first month of operations the following transactions were recorded: January 10 Purchased 2 sport model bikes for $200 each plus shipping charges totaling $20. The total invoice was $420. January 30 Purchased 2 sport model bikes for $220 each plus shipping charges totaling $20. The total invoice was $460. At the end of January, a physical inventory revealed that there was one sport model bike on hand. (Three bikes were sold during the month.) Assuming the use of FIFO inventory method, compute the COST OF GOODS SOLD for the month.

I know the answer is $650- what are the steps to get to this answer?