The average score of the spelling test rounded to one decimal place is 90.60.
The average score is the sum of a set of numbers divided by the total number in the dataset.
Average score = sum of scores / number of students that took the test
(100+ 100 + 95 + 95 + 95 + 95 + 95 + 95 + 95 + 95 + 95 + 90 + 90 + 90 + 90 + 90 + 90 + 90 + 90 + 90 + 90 + 80 + 80 + 80 + 70) / 25 = 90.60
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