Is the integer k divisible by 4?
(1) 8k is divisible by 16
in other words:
8k/16 is an integer
dividing top and bottom by 8:
k/2 is an integer
Well, we know that k must be divisible by 2, but it may or may not be divisible by 4: insufficient.
(2) 9k is divisible by 12
in other words:
9k/12 is an integer
dividing top and bottom by 3:
3k/4 is an integer
Well, there's no way the "4" could come from the "3" part of "3k", so for 3k/4 to be an integer, k/4 must be an integer. Therefore, k is definitely divisible by 4: sufficient.
(2) is sufficient but (1) isn't: choose (B).
Division
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Stuart@KaplanGMAT
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vishubn
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stem is K is divisible by 4 sooo k can ne multiple of 2,4
A) 8k/16
in other wrds k/2.....
k is multiple of 2
k=2 T
k=4 F
Insufff
B) 9k/12 -- > 3k/4
that is plugin values
k=1, No
k=2 no
k-3 no
4=4 only
YEs
SO B is suff
Vishu
A) 8k/16
in other wrds k/2.....
k is multiple of 2
k=2 T
k=4 F
Insufff
B) 9k/12 -- > 3k/4
that is plugin values
k=1, No
k=2 no
k-3 no
4=4 only
YEs
SO B is suff
Vishu
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ronniecoleman
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is k divisible by 4
8k diviisible by 16
9k is divisible by 12
8 k == 2*2*2* k
16= 2*2*2*2
So k should have atleast one more 2
Not suff
9K = 3*3*k
12 = 4*3
So k has to have atleast one 4
Suff
8k diviisible by 16
9k is divisible by 12
8 k == 2*2*2* k
16= 2*2*2*2
So k should have atleast one more 2
Not suff
9K = 3*3*k
12 = 4*3
So k has to have atleast one 4
Suff
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vittalgmat
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Great job explaining Ronnie.ronniecoleman wrote:is k divisible by 4
8k diviisible by 16
9k is divisible by 12
8 k == 2*2*2* k
16= 2*2*2*2
So k should have atleast one more 2
Not suff
9K = 3*3*k
12 = 4*3
So k has to have atleast one 4
Suff
Thank you for being accomodative.
