Question

If the digits of a three-digit number are reversed in order, then the sum of the new resulting number and the original number comes out to be 665. The difference of the two numbers is 297. The tens digit place is two times the hundreds place digit. What is the number?

Answer 1

y + x = 665
|x - y| = 297
x = 665 - y
|665 - y - y| = 297
|665 - 2y| = 297
Path 1:
665 - 2y = 297
-2y = -368
y = 184

Path 2:
665 - 2y = -297
-2y = 962
y = 481

So y is either 184 or 481. 
Now, lets check
the tens place is 2 times the hundreds place
That rules out 184
Leaving us with 481 as our final answer