<prompt> The ratio of anaerobe to aerobes in stool is10:01100:01:001000:01:0010000 : 1  <response>: The mean number of bacteria in colon exceeds 1011 bacteria gram of faecal matter. Approximately 99.9 of these bacteria are anaerobic in the colon. 300 to 400 different species or types of bacteria can be found. So the ratio of anaerobes to aerobes in the stool is 1000:01. Ref: Baveja textbook of microbiology; 4th edition. 