Difference between revisions of "2016 AMC 10A Problems/Problem 7"
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As <math>x</math> is the mean, <cmath>\begin{align*} | As <math>x</math> is the mean, <cmath>\begin{align*} | ||
x=\frac{60+100+x+40+50+200+90}{7} | x=\frac{60+100+x+40+50+200+90}{7} | ||
− | &\ | + | &\rightarrow x=\frac{540+x}{7} \\ |
− | &\ | + | &\rightarrow 7x=540+x \\ |
− | &\ | + | &\rightarrow 6x=540 \\ |
− | &\ | + | &\rightarrow =\boxed{\textbf{(D) }90.} |
\end{align*}</cmath> | \end{align*}</cmath> | ||
+ | ==Check== | ||
+ | Order the list: <math>\{40,50,60,90,100,120\}</math>. <math>x</math> must be <math>60</math> or <math>90</math> because it is the median and mode of the set. Thus <math>90</math> is correct. | ||
==See Also== | ==See Also== |
Revision as of 15:12, 4 February 2016
Contents
Problem
The mean, median, and mode of the data values are all equal to . What is the value of ?
Solution
As is the mean,
Check
Order the list: . must be or because it is the median and mode of the set. Thus is correct.
See Also
2016 AMC 10A (Problems • Answer Key • Resources) | ||
Preceded by Problem 6 |
Followed by Problem 8 | |
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 AMC 10 Problems and Solutions |
2016 AMC 12A (Problems • Answer Key • Resources) | |
Preceded by Problem 3 |
Followed by Problem 5 |
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 AMC 12 Problems and Solutions |
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