functions g(g(g(g(g(x))))) = 19

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functions g(g(g(g(g(x))))) = 19

by pappueshwar » Sun Feb 05, 2012 1:00 am
hi all,
request if any one can give an easier solution to understand the below probelm

The function g(x) is defined for integers x such that if x is even, g(x) = x/2 and if x is odd, g(x) = x + 5. Given that g(g(g(g(g(x))))) = 19, how many possible values for x would satisfy this equation?

choices:
A) 1
B) 5
C) 7
D) 8
E) 11

[Moderator Edit: Moving the post to GMAT Math -> Problem Solving]
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by Mike@Magoosh » Sun Feb 05, 2012 11:51 am
Hi, there. :)

You can see my full solution to this question at

https://www.beatthegmat.com/function-pro ... 02358.html

Please let me know if you have any questions.

Mike :)
Magoosh GMAT Instructor
https://gmat.magoosh.com/

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by neelgandham » Mon Feb 06, 2012 5:45 am
Hey Eshwar,

You can see my solution here -> https://www.beatthegmat.com/functions-t102958.html.
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by Anurag@Gurome » Mon Feb 06, 2012 7:31 am
pappueshwar wrote:hi all,
request if any one can give an easier solution to understand the below probelm

The function g(x) is defined for integers x such that if x is even, g(x) = x/2 and if x is odd, g(x) = x + 5. Given that g(g(g(g(g(x))))) = 19, how many possible values for x would satisfy this equation?

choices:
A) 1
B) 5
C) 7
D) 8
E) 11

[Moderator Edit: Moving the post to GMAT Math -> Problem Solving]

Image

The correct answer is D.
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