numbers and function combined

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numbers and function combined

by quantskillsgmat » Sun Dec 25, 2011 2:26 am
Q)For two positive integer a and b define the function h(a,b) as the greatest common factor of a,b.let A be set of n positive integers,G(A) the gof of elements of set A is computed by repeatedly using the function h.The minimum number of times h is required to be used to compute G is
a)n/2 b)n-1 c)n d)none
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by user123321 » Sun Dec 25, 2011 6:29 am
quantskillsgmat wrote:Q)For two positive integer a and b define the function h(a,b) as the greatest common factor of a,b.let A be set of n positive integers,G(A) the gof of elements of set A is computed by repeatedly using the function h.The minimum number of times h is required to be used to compute G is
a)n/2 b)n-1 c)n d)none
[spoiler]IMO B?[/spoiler]

take for example few numbers 2,3,4,5,6,7
and start finding gdc using 2 numbers at a time, you need to do it atleast 5 times.
take for example few numbers 2,3,4,5,6,7,8
then it requires atleast 6 times.

so by this we need to use the function n-1 times.

user123321
Just started my preparation :D
Want to do it right the first time.