Four sizes of scaled text are shown.

four rows of text and numbers. the first row contains the number two point six one eight followed by the phrase website text size. the next row contains a question mark followed by the phrase website text size, but smaller than the previous row. the third row contains the number one followed by the phrase website text size, but smaller than the previous row. the fourth row contains the number zero point six one eight followed by the phrase website text size, but smaller than the previous row.

what is the unknown scale size?

enter your answer as a decimal in the box. round only your final answer to the nearest thousandth.