OG详解-OG10 数学1 Q25

Choice D is correct. It’s given that the result of increasing the quantity x by 1,800% is 684. It follows that x + 1,​800100​x = 684, which is equivalent to x+18x = 684, or 19x = 684. Dividing each side of this equation by 19 yields x = 36. Therefore, the value of x is 36.
Choice A is incorrect. The result of increasing the quantity 12,996 by 1,800% is 246,924, not 684. Choice B is incorrect. The result of increasing the quantity 12,312 by 1,800% is 233,928, not 684. Choice C is incorrect. The result of increasing the quantity 38 by 1,800% is 722, not 684.