Final answer:
The mode score of 87 on a 7th-grade math test means that 87 is the number that appears most frequently in the score list. It's not related to the average, highest, or a specific passing score, but simply indicates the most common score among all the test results.
Step-by-step explanation:
If the mode score on the 7th-grade math test was 87, it means that 87 is the most frequent score among all students who took the test. This does not necessarily reflect the average score (mean), nor does it indicate the highest or lowest scores achieved by the students. The mode is simply the number that occurs most frequently in a given set of data. Therefore, the correct answer is a) 87 is the most frequent score among all students.
Understanding descriptive statistics, such as the mean, median, and mode, is essential in interpreting data. The mean provides an average value, the median gives the middle score when the data is ordered, and the mode shows the most common value. It's also important to note that a set of data may have no mode if no number repeats or if all numbers occur with the same frequency.