# Can you solve the riddle

Can you solve the mathematics puzzle? • Hey! Welcome to Puzzling.SE :D may you please provide a source of this puzzle? – QuantumTwinkie Sep 29 '18 at 0:04
• The image is so cropped, how can we know whether the number on the left is 12 or 112? – Jaap Scherphuis Sep 29 '18 at 0:51

The 12 is a bit strange, so I just assume that it's the 2 that got cropped out (if its not then this answer doesn't work). I believe it is since the following image I found is similar:

But assuming it is, we have:

74 = 64 + 6 + 4, 85 = 74 + 7 + 4, 98 = 85 + 8 + 5, 115 = 98 + 9 + 8, 122 = 115 + 1 + 1 + 5 (The next number is the previous plus its digit sums).

• If you look at the way the image is cropped, it looks like there could be a digit before the 12, so it can't be a 2 that is cropped from 122. – nikki Sep 29 '18 at 2:29
• @nikki That's what I thought too so I googled for similar images and found that one to make sure, if that's not the case I don't know. – simonzack Sep 29 '18 at 2:31
• It is likely a buggy app that just couldn't fit the number in the available space and lopped off the last digit. I think the puzzle image you found is near to being proof of that. – Jaap Scherphuis Sep 29 '18 at 3:09