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40 votes
40 votes
Pls answer 90 points if you do

Alicia received the following seven scores on her math assignments.

80, 90, 10, 75, 90, 95, 99

Find the mean and median. Which measure of center best represents the data?
the mean
the median
both the mean and the median
neither the mean nor the median

User EJS
by
2.9k points

2 Answers

21 votes
21 votes

Answer:

  • Mean = 77
  • Median = 90
  • Median is the best measure of center

Explanation:

Mean

The sum of all data values divided by the total number of data values.


\implies \textsf{Mean}=(80+90+10+75+90+95+99)/(7)=(539)/(7)=77

Median

The middle value when all data values are placed in order of size.

Scores in order of size: 10, 75, 80, 90, 90, 95, 99

The middle value is 90, therefore Median = 90

Conclusion

From inspection of the scores, it appears that the score of 10 may be an outlier, since it is a long way from the majority of the other values in the data set. The mean can be heavily affected by outliers, whereas the median is not affected by outliers. Therefore, the median is the measure of center that best represents this set of data.

User Xiaojun Chen
by
2.4k points
27 votes
27 votes

Hey there!


QUICK RUNDOWN OF EACH MEANING:
• To find your mean, you have to ADD up all of your numbers and DIVIDE it by the total numbers you have in your data plot. So, when you hear/see the word “mean” (in mathematics) think of its asking what is the average/total number

• To find the median you have to find you have to put your numbers from least (smallest) to greatest (biggest). So when you hear/see the word “median” (in mathematics) think of its asking you what is the number in the middle/center in the data plot.

SOLVING FOR THE MEDIAN:

Original set:

80, 90, 10, 75, 90, 95, 99

Conversion:

10, 75, 80, 90, 90, 95, 99


CALCULATE IT!

Therefore, your mean should be: 90


SOLVING FOR THE MEAN:

Original set:

80, 90, 10, 75, 90, 95, 99

The equation:

(80 + 90 + 10 + 75 + 90 + 95 + 99) / 7


CALCULATE IT!

(80 + 90 + 10 + 75 + 90 + 95 + 99) / 7

= 170 + 10 + 75 + 90 + 95 + 99) / 7

= (180 + 75 + 90 + 95 + 99) / 7

= (255 + 90 + 95 + 99) / 7

= (345 + 95 + 99) / 7

= (440 + 99) / 7

= 539 / 7

= 77

Therefore, the mean is: 77



Therefore, your overall answer should be: Median


Good luck on your assignment & enjoy day!


~Amphitrite1004:)

User Rottitime
by
3.0k points