The conversation between human and AI assistant.
How did the " _ + _ + _ = 30 using 1, 3, 5, 7, 9, 11, 13 and 15" riddle become so popular?
That's interesting. Do you have any idea who came up with this riddle?
There is no clear source of the riddle, and it's not clear when it first appeared. However, it is likely that it has been circulating for quite some time, and with the rise of social media platforms, it has gained more popularity recently.