OG详解-OG3 数学2 Q19

Choice B is correct. It’s given that the minimum value of x is 12 less than 6 times another number n. Therefore, the possible values of x  are all greater than or equal to the value of 12 less than 6 times n. The value of 6  times n is given by the expression 6n. The value of 12 less than 6n is given by the expression 6n -12. Therefore, the possible values of x are all greater than or equal to 6n -12. This can be shown by the inequality x ≥6n -12.
Choice A is incorrect. This inequality shows the possible values of  x  if the maximum,not the minimum, value of x is 12 less than  6 times  n. Choice C is incorrect. This inequality shows the possible values of x if the maximum, not the minimum, value of x is 6 times n less than 12, not 12 less than 6 times n. Choice D is incorrect. This inequality shows the possible values of  x  if the minimum value of x  is  6 times n less than 12, not 12 less than 6 times n.