x < 6 or x > 10 For option a: 6.1 is neither less than 6 nor greater than 10 For option b: all numbers are either less than 6 or greater than 10 For option c: 9.8 is neither less than 6 nor greater than 10 For option d: 8.5 and 9.1 are neither less than 6 nor greater than 10