2019 AMC 8 Problem 10
Below is the video solution and professionally curated solution for Problem 10 of the 2019 AMC 8, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2019 AMC 8 solutions, or check the answer key.
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Difficulty rating: 1020
10.
The diagram shows the number of students at soccer practice each weekday during last week. After computing the mean and median values, Coach discovers that there were actually participants on Wednesday. Which of the following statements describes the change in the mean and median after the correction is made?
The mean increases by and the median does not change.
The mean increases by and the median increases by
The mean increases by and the median increases by
The mean increases by and the median increases by
The mean increases by and the median increases by
Video solution:
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Written solution:
There are more participants, which means the mean is increased by
Right now, we can see that the median is If gets replaced with then the median becomes
This shows that the median is also increased by
Thus, the correct answer is B.
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