Josh and his friends bought vanilla wafers for $4 per packet and chocolate wafers for $1 per packet at a carnival. they spent a total of $45 to buy a total of 27 packets of wafers of the two varieties.

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.