A teacher returns an exam with possible scores ranging from 0 to 100 . The students suspect that the majority of them performed poorly on the exam and request summary statistics. The teacher provides the mean, which was 72 , as a summary statistic. A total of 400 students took the exam. Some of the students find the mean to be high, based on talking to other students. They take a random sample of 15 students, and they find that the mean equals 71.5 while the median equals 62 . Based on this result, we conclude that:

Step-by-step explanation:

If the mean of 15 students is 71.5, then total score = 15 X 71.5 = 1072.5

The median score is 62, meaning that, the combined score of two students = 62 X 2 = 124

The difference of 1072.5 and 124 = 948.5, this represents the total score of 13 other students

∴ The mean score of 13 students = 948.5/13 = 73

In conclusion, it was only very few students that took the exam and majority of other students absconded from the exam. Majority of students scored averagely above 70.

10 miles

step-by-step explanation:

8(-10x+3.5y-7)

8×-10x + 8×3.5y + 8×-7

-80x + 28y - 56

therefore

-80x+28y-56 is the correct answer