Tracey paid $135 for an item that was originally priced at $510. what percent of the original price did tracey pay. round to the nearest tenth of a percent.

Actually Welcome to the Concept of the Statistics of a Categorised data.

We know that medium is the middle most point of any observation table or a Histogram displayed,

Hence we can clearly see here that, observation - 4 on the x-axis is the middle most entry of the Histogram, around which all other entries are equal.

===> Hence, option A.) 4 is correct answer.