russ9 wrote:
what is the value of the two-digit positive integer n?
1)The sum of the digits in n is 12
2)If the digits in n are reversed ,the value of the number formed is 36 more than the value of n
I'm having a hard time setting up this problem, wondering if ya'll could help me out:
1) a + b = 12 = insuff
2) a + b + 36 = b + a == this just gives me an equation that is "0=36" which I don't understand?
OA is C.
Thanks!
1) sum of the digits in n is 12, that means : 39,48,57,66,75,84,93- not sufficient
2) this means : 10a + b = 10b + a - 36 => 9a=9b-36
a+4 =b, so b is 4 more than a and difference is 36, such as : 15 & 51, 26 & 62, 37 & 73, 48 & 84, ... - not sufficient
1 + 2, we have only one common answer 48 & 84.
So answer is C