Answer :
Based on the data, the correct option is B. The students typed less than predicted by 38.8 words per minute.
How do we find whether the students typed more or less than the instructor predicted?
To determine whether the students typed more or less than the instructor predicted, we will calculate the average words per minute typed by the students in the sample.
To find the average, we shall sum up the words per minute typed by each student and divide by the number of students (10):
Average = (35 + 44 + 38 + 27 + 65 + 40 + 31 + 53 + 25 + 30) / 10
Average = 388/10
Average = 38.8 words per minute.
Hence, the students typed, on average, 38.8 words per minute, which is less than the instructor's guarantee of 40 words per minute.
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