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- General GMAT Strategies - 7 videos (free)
- Data Sufficiency - 16 videos (free)
- Arithmetic - 38 videos
- Powers and Roots - 36 videos
- Algebra and Equation Solving - 73 videos
- Word Problems - 48 videos
- Geometry - 42 videos
- Integer Properties - 38 videos
- Statistics - 20 videos
- Counting - 27 videos
- Probability - 23 videos
- Analytical Writing Assessment - 5 videos (free)
- Reading Comprehension - 10 videos (free)
- Critical Reasoning - 38 videos
- Sentence Correction - 70 videos
- Integrated Reasoning - 17 videos
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Comment on Ages of Ann, Bea and Cho
Couldn't you put 9 and 1 as
If we made 9 and 1 the other
If we made 9 and 1 the other two values in the third example (for statement 2), then the three numbers would be {1, 9, 10}, in which case the average would NOT equal 10 (one of the given conditions).
I see the way you did it.
Yes, that's an easy trap to
Yes, that's an easy trap to fall into :-)
Cheers,
Brent
I wish this test wasn't all
Ha! Yes, it certainly seems
Ha! Yes, it certainly seems that way at times!!
Cheeky. So very cheeky. Fell
It's an enticing answer
It's an enticing answer choice!!
Hi brent,
I have learned that in arithmetic sequence the mean is always equal to median if its in odd number of sequence please correct me if i am wrong
You're partially correct.
You're partially correct.
For ALL sequences in which the values are EQUALLY SPACED, the mean = the median.
It doesn't matter whether we have an odd or even number of values.
For example, in the set {3, 8, 13, 18}, the mean = the median = 10.5
This is covered in the following video: https://www.gmatprepnow.com/module/gmat-statistics/video/804
By the way, the GMAT doesn't expect students to know the term "arithmetic sequence."
Cheers,
Brent
Darn it Brent, made the
Also, thanks for this comment. In your previous video, there was a reinforcement question that heeded to this rule which you explained in your gmat club solution but definitely had no idea how to solve without that rule.