I've seen different variations of this question before thats how I know this is the right answer, but can someone explain to me how/why its true?
thanks
LCM & GSF DS probelm
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1 - insufficient. take d=2, d=3. 100 and 1000 are factors of 30!
2 - insufficient. again, d could be anything
30! has 7 zeroes (5*2, 10, 15*4, 20, 25*8, 30 all yield zeroes). So,
knowing that d>6 is sufficient
Is it C
2 - insufficient. again, d could be anything
30! has 7 zeroes (5*2, 10, 15*4, 20, 25*8, 30 all yield zeroes). So,
knowing that d>6 is sufficient
Is it C
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- Master | Next Rank: 500 Posts
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I was wondering where GCF and LCM are in the previous questionxcise_science wrote:oops sorry, I attached the wrong image.
here's the right one.
Is it possible to delete the old one?
Thanks
Product of 2 numbers = LCM * GCF
[ For reference: https://en.wikipedia.org/wiki/Greatest_c ... ng_the_gcd ]
So, using (1) and (2), you can see that the product is a multiple of 8.
We can clearly see that either (1) or (2) by itself is not sufficient