Astray dog 18 of your muffins. that was 2/3 of them . with how many did u start with

27 because half of 18 would be 1/3 of your muffins, 1/3 of the muffins is 9 and add that third to the 2/3 and you're back to your original amount.

The first one, i believe, would be correct. all the others have one thing in common, and that's that they have repeating numbers. in the second one, x and y have repeating 6's and 3's, and in the third, x and y have repeating 6's as well. in the last one, there are repeating 3's. the first one has no repeating numbers.