OG详解-OG7 数学2 Q2

Choice B is correct. It’s given that there are 250 trees in a park and of these trees, 6% are birch trees. The number of birch trees in the park can be calculated by multiplying the number of trees in the park by6100​​ . Therefore, the number of birch trees in the park is 250(6100​​), or 15.
Choice A is incorrect. This is the percentage of trees in the park that are birch trees, not the number of birch trees in the park. Choice C is incorrect. This is 30%, not 6%, of 250. Choice D is incorrect and may result from conceptual or calculation errors.