Quibble

"This is a very very rare 50 yen coin whose head is on the tail and whose tail is on the head."



"I will give you this 50 yen instead of a 100 yen coin."



It's easy to laugh at Nobita. We might need to admire him because of his innocence. Anyway, if you can read Japanese, the website about Doraemon may crack you up.

http://hendora.com/hendora/hendora09/hendora9.htm