Answer:
Let´s say we need to compare the exam result of two separate groups of students. Each group has 3 students, and both groups have an average result of 70 over one-hundred.
All the students from group A had a score of 70
(70+70+70)/3=70 average
But the score from group B are
student 1: 40 over 100
student 2: 70 over 100
student 3: 100 over 100
(40+70+100)/3=70 average
As we can see, even though both groups have the same average score, there´s a hidden disparity that can not be recognized with only the average.
Explanation:
In statistics, an average is a number that estimates the central tendency of a given set of numbers, and it can also be described as the summary of a group of numbers as a single number. While averages can be useful for comparison, they can also hide disparities that required further analysis with different estimations.