[informal007]

>So Sandy knows the answer isn't (5,5). Similarly, she knows it's not (2,8) or (3,7).

Why is not (2,8)? both pair (2, 8) and pair (4, 4) can produce a product of 16.

Thanks anyway!

[indecisive_user]

Yup, you're right, I missed that pair. But hopefully you get the general point on how it works :)

[informal007]

I get it from (this blog)[https://alexanderell.is/posts/numbers-game/], Thanks very much still!

[informal007]

sorry, I still can't get it...

> Yes, the pair (2,9) sums to 11, but the product is unique, and if Peter had been given the product 18 to begin with, he would have immediately known the answer.

pair (2,9) and pair (3,6) can produce a product of 18, so Peter can't immediately know the answer if he had been given the product 18 to begin with, so the problem can't beed solved.

I think this problem would Caught in an unresolved cycle after unique product and unique sum has been ruled out.

I don't know where i am wrong, Sincere thanks...