2019 AMC 8 Problems/Problem 10
Contents
Problem 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 .
Solution
On Monday, people come. On Tuesday, people come. On Wednesday, people come. On Thursday, people come. Finally, on Friday, people come. , so the mean is . The median is . The coach figures out that actually people come on Wednesday. The new mean is , while the new median is . Also, the median increases by because now the median is instead of . The median and mean both change, so the answer is .
Another way to compute the change in mean is to notice that the sum increased by with the correction. So, the average increased by .
Video Solution by Math-X (First fully understand the problem!!!)
https://youtu.be/IgpayYB48C4?si=Al-ATwscPJRaKEtF&t=3094
~Math-X
The Learning Royal : https://youtu.be/8njQzoztDGc
Video Solution 2
Solution detailing how to solve the problem: https://www.youtube.com/watch?v=vkm1ZXuuQcc&list=PLbhMrFqoXXwmwbk2CWeYOYPRbGtmdPUhL&index=11
Video Solution 3
~savannahsolver
Video Solution by OmegaLearn
https://youtu.be/TkZvMa30Juo?t=2171
~ pi_is_3.14
Video Solution (CREATIVE THINKING!!!)
~Education, the Study of Everything
Video Solution by The Power of Logic(Problem 1 to 25 Full Solution)
~Hayabusa1
See Also
2019 AMC 8 (Problems • Answer Key • Resources) | ||
Preceded by Problem 9 |
Followed by Problem 11 | |
1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 | ||
All AJHSME/AMC 8 Problems and Solutions |
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