OG11-Q195
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Source: Beat The GMAT — Problem Solving |
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givemeanid
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He goes up 3 times and moves right 2 times. Just by counting, I seem to be getting 10. What is OA?
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givemeanid
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Yes there is.
We essentially need a 5 letter word which will denote the path. The letters in the word should be R, R, U, U, U. The order matters and Rs and Us are indistinguishable.
To find the number of distinct permutations of a set of items with indistinguishable items, divide the factorial of the items in the set by the product of the factorials of the number of indistinguishable elements.
That is 5! / (2! * 3!) = 10.
We essentially need a 5 letter word which will denote the path. The letters in the word should be R, R, U, U, U. The order matters and Rs and Us are indistinguishable.
To find the number of distinct permutations of a set of items with indistinguishable items, divide the factorial of the items in the set by the product of the factorials of the number of indistinguishable elements.
That is 5! / (2! * 3!) = 10.
So It Goes
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discreet
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Again,To all my dear members,Here's a general concept that can be used for such type of questions.
I firmly believe that one must always attack the concept first rather than attacking a specific question.So,when I saw this problem,I started searching for a concept that I can use for this problem.
So,here it is : Refer image
This is a part of my personal Flashcards, sharing it now
There's one more similar problem : distance between 2 cities PS pblm...but that's a simpler one that can be easily deduced.
I firmly believe that one must always attack the concept first rather than attacking a specific question.So,when I saw this problem,I started searching for a concept that I can use for this problem.
So,here it is : Refer image
This is a part of my personal Flashcards, sharing it now
There's one more similar problem : distance between 2 cities PS pblm...but that's a simpler one that can be easily deduced.
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manu singhal
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What are th number of the bottom right of C imply mathematically?
