Choose two distinct non-zero digits. Evaluate the sum of the product and the s.o.d. of the pair.

What is the probability that the result is the concatenation of the initially selected digits?

Example: if the digits were 4,7 the resulting 4*7+7+4=39, not the case you were after, i.e. 47 or 74

(In reply to Solution by Larry)

Choose the two digit number concatenated as ab.  Which is actually 10a+b.  Then we have

Posted by Jer on 2022-06-17 09:46:16