Meera's marks in three tests are 8, 9, 9 (out of 10)
Meera's marks in three tests are 8, 9, 9 (out of 10). She finds the average: (8+9+9)/3 = 8.67. Then she says "that's wrong — none of my tests scored 8.67". Her brother says an average does not have to be one of the values in the list. Who is right?
Who do you think is right? Pick one.
The answer: Her brother is right, an average often lands in between and can be a decimal
Why
Meera is expecting the average to be a number she can point to in her list of marks, but that is not what an average is. The average is a balancing point: you pool all the marks together and share them out equally, so it represents the whole set rather than any single test. That balancing point very often sits BETWEEN the actual values, and it can be a decimal even when every mark is a whole number. Test it: her marks total 8+9+9 = 26; shared equally across 3 tests that is 26/3 = 8.67, which is correct — it just falls between her 8 and her 9s, exactly where a balancing point should. Her brother is right: an average commonly lands in between the data and can be a decimal — it is not required to be one of the values in the list.
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