The sum of the digits of a two-digit number is 12. The number formed by interchanging the digits is 54 more than the original number.

What is the original number?

39
48
57

Question

The sum of the digits of a two-digit number is 12. The number formed by interchanging the digits is 54 more than the original number.

What is the original number?

39
48
57

anonymous · Answer

39?

astrophysics · Answer

Hey, can you show how you got that?

tkhunny · Answer

Really?  Guess and check?  No need to be fancy.

anonymous · Answer

i did this before winter break... i dont remember how i did it. I was making sure I did t right

anonymous · Answer

no guessing was involved @tkhunny

anonymous · Answer

It's pretty simple. The only possible pairs are 3+9,4+8, and 5+7. So 39, 48, and 57 are the initial pairs. The inverses are this 93, 84, and 75. 93 is pretty clearly the only one above 50, so it must be it.

anonymous · Answer

so i was right?

anonymous · Answer

Well yeah.

anonymous · Answer

thank you:)

anonymous · Answer

ye no problem (:

tkhunny · Answer

That's pretty much guessing, but there's only 3 choices, so no big.