The mean is the average of a set of numbers.
So if the remaining 40% of students score 100 points, and the 60% score like 50 points, then the mean would still be 70 points because of the 40% of students that scored super high.
So yes, it can be true.
Low-birthweight i believe.
It would be negative 5 since it is going down.
Statistic significance requires that your sample be representative of the population, but I'm struggling with this because if the class is an elective then the answer would be: <span>No, it is not a valid inference because she asked all 22 students in her science class instead of taking a sample of the students in her school.
BUT if the class is required, as most science classes are, then it WOULD be a random sample of the school. So the last option would be correct.
My guess though is that the teacher is looking for answer B.
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