Sets, Progressions, Combinations

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Sets, Progressions, Combinations

by coolhabhi » Mon Feb 27, 2012 5:14 am
Given a set
A = {1, 3, 9, 27, 81, -----, (3)^100}

Y is a subset of A such that the GEOMETRIC mean of no two numbers is (3)^50. N is the maximum possible number of elements in set Y.

1) What is the value of N?
A) 50
B) 51
C) 49
D) 52

2) In how many ways can the set Y be formed such that it has exactly N elements?
A) (2)^50
B) (2)^51
C) (3)^50
D) (3)^51

Source: A test booklet which I recently found.
Source: — Problem Solving |

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by Brent@GMATPrepNow » Mon Feb 27, 2012 9:18 am
This is a duplicate post.

Solutions/discussions can be found here: https://www.beatthegmat.com/sets-progres ... 07126.html

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
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