Step by step work out, please!!! I I really want to understand how to get to the answer!!

19. Company X applied LIFO and reported gross profit of $400,000. Company X reported inventory of $100,000 at January 1 and $120,000 at December 31. Had FIFO had been used rather than LIFO, those figures would have been $180,000 and $262,000 at January 1 and at December 31, respectively. What would Company X's gross profit have been under FIFO? $318,000 B. $328,000 C. $338,000 D. $462,000 E. $482,000