Simone saved $15.45 from her allowance, had $7.37 in her piggy bank, and had $22.55 left from her birthday. How much money does Simone have?

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.

Understanding what? lol