The number is 10t+2t = 12t. Reversing the digits, 10*(2t) + t = 21t. 21t - 12t = 27 9t = 27 t = 27/9 = 3. ANSWER. The number is 36. CHECK. The reversed number is 63, and it is 63 - 36 = 27 units greater than the original number. ! correct !
The first sentence tells you it's either 12,24,36, or 48 Its reverse would then be 21,42,63, or 84 The only one that differs from its reverse by 27 is 36, (since 63-36=27), so the answer is 36. With a little practice you can do problems like this in your head or just by jotting down a tiny bit, and you'll have the answer before you even begin to solve it. Edwin