Question 1125339
<br>
12 years ago, the sum of their ages was 72-2(12) = 48.<br>
Logical reasoning or a bit of simple algebra then tells us that, since Gregory was at that time twice as old as Zoe, Gregory was 32 and Zoe was 16.<br>
Since that was 12 years ago, their ages now are 44 and 28.<br>
ANSWER: Gregory is now 44