Sally has a pet snail that snail fell in the well the well is 16 feet deep. each day the snail climbs up 5 feet but each night it slides down 4 feet. how many days will it take for sally's snail to get to the top of the well

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.