There is an Ida Rix in the 1930 Denver, Denver Co., CO census. She is single, born Iowa, parents born Germany. She was a washwoman. In 1910, she was living on Walnut Street in Denver, and doing general housekeeping. There is a marriage for an Ida M. Rix to Herbert J. Meis, but she is 18 years old when she marries him on Jan. 16, 1911, making her born about 1893, so that does not look to be yours. THey moved to Pueblo. Have you looked back in Iowa? If she was single and had no descendants, she may have been interred in Iowa.