statistic

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statistic

by teejaycrown » Sat Oct 20, 2012 12:02 pm
What is the average arithmetic mean of eleven consecutive integers
1. The average of the first nine integers is 7
2. The average of the last nine integers is 9
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by TheGmatTutor » Sat Oct 20, 2012 1:27 pm
Since they are consecutive integers and we have an odd number of integers (11), the mean will be equal to the median. In other words, the middle number will be the average of the whole set. Thus, each statement allows you to determine the whole set, and each statement is sufficient to determine the average. Answer is D.
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