Jaiden made an error in ordering the numbers, and the correct statement that describes his error is:
Jaiden should have added zeroes to the ends of the shorter decimals to get 2.615, 2.650, 2.700, and 2.623. Then, he should have compared all of them using place value.
This approach would allow for a direct comparison based on the same number of decimal places. By ensuring all numbers are represented with the same number of digits after the decimal point, Jaiden could have accurately ordered them from least to greatest.