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Re: If the positive integer x is a multiple of 3 and the positive integer
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24 Sep 2022, 05:49
x = 3k (where k is a positive integer)
y = 4z (where z is a positive integer)
xy = 12kz = 3*2*2 kz
Now let us take a look at the options
I. 6
xy already contains a 3 and a 2 so IT MUST BE A MULTIPLE OF 6
II. 9
xy contains one 3 so if k/z contains a 3, then it can be a multiple of 9, else not. So, not certain
III. 12
xy already contains a 3 and two 2's so IT MUST BE A MULTIPLE OF 12
Answer - D