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Re: D0120 [#permalink]
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10 Dec 2016, 11:21
This is a little confusing. If factorial is not defined for negative numbers, then a and b must be positive.



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Re: D0120 [#permalink]
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17 Feb 2017, 06:34
BunuelAs per the solution given: (1) The median of {a!, b!, c!} is an odd number. This implies that b!=odd. Thus b is 0 or 1. But if b=0, then a is a negative number, so in this case a! is not defined. Therefore a=0 and b=1, so the set is {0!, 1!, c!}={1, 1, c!}. Now, if c=2, then the answer is YES but if c is any other number then the answer is NO. Not sufficient. it says b is 0 or 1. Is 0 an odd number?



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Re: D0120 [#permalink]
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17 Feb 2017, 09:05
Darkhorse12 wrote: BunuelAs per the solution given: (1) The median of {a!, b!, c!} is an odd number. This implies that b!=odd. Thus b is 0 or 1. But if b=0, then a is a negative number, so in this case a! is not defined. Therefore a=0 and b=1, so the set is {0!, 1!, c!}={1, 1, c!}. Now, if c=2, then the answer is YES but if c is any other number then the answer is NO. Not sufficient. it says b is 0 or 1. Is 0 an odd number? 0 is an even integer. But 0! = 1 = odd.
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Re: D0120 [#permalink]
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22 Apr 2017, 21:29
How is 0 factorial 1?



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Re: D0120 [#permalink]
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23 Apr 2017, 03:41



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Re: D0120 [#permalink]
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10 May 2017, 11:41
How can we determine that c must be 2 (not any other prime number) from the :
2) c! is a prime number.



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Re: D0120 [#permalink]
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10 May 2017, 11:53



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Re: D0120 [#permalink]
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10 May 2017, 11:56
My bad... stupid mistake, thanks anyway !



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Re: D0120 [#permalink]
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15 Jun 2017, 07:05
Bunuel wrote: If a, b, and c are integers and \(a \lt b \lt c\), are a, b, and c consecutive integers?
(1) The median of {a!, b!, c!} is an odd number.
(2) c! is a prime number. Love your explanation.



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Re: D0120 [#permalink]
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07 Aug 2017, 05:52
In this question, what we know from statement A is that b! is odd. So b could either be 0 or 1.
If b is 0, then a can still assume the value 0. a does not have to be negative.
The second statement tells us that c is 2, but gives no details on a and b.
Combining both the statements still gives us three possible values for {a!,b!,c!}:
I: {0!,0!,2!} II: {0!,1!,2!} III: {1!,1!,2!}
I and III would mean that the answer is NO and II would mean the answer is YES.
Going by this logic, I went with E.
Can anyone please correct me and explain how the answer is C? I do not understand any of the given explanations.



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Re: D0120 [#permalink]
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07 Aug 2017, 16:50
anirudhb94 wrote: In this question, what we know from statement A is that b! is odd. So b could either be 0 or 1.
If b is 0, then a can still assume the value 0. a does not have to be negative.
The second statement tells us that c is 2, but gives no details on a and b.
Combining both the statements still gives us three possible values for {a!,b!,c!}:
I: {0!,0!,2!} II: {0!,1!,2!} III: {1!,1!,2!}
I and III would mean that the answer is NO and II would mean the answer is YES.
Going by this logic, I went with E.
Can anyone please correct me and explain how the answer is C? I do not understand any of the given explanations. Notice that we are told that a < b < c, so I and III are not possible, which leaves only a=0, b=1 and c=2.
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Re: D0120 [#permalink]
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09 Aug 2017, 00:47
Factorial of a number is prime Can it be anything elses besides 2!? Or 2! is the only factorial of a number is prime?



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Re: D0120 [#permalink]
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09 Aug 2017, 00:50



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Re D0120 [#permalink]
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09 Sep 2017, 15:00
I don't agree with the explanation. i think A should be the answer because a set (1,1,c!) will have a median of 1 always na



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Re: D0120 [#permalink]
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09 Sep 2017, 15:07



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Re D0120 [#permalink]
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13 Oct 2017, 12:18
I think this is a highquality question and I agree with explanation.



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Re D0120 [#permalink]
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19 Nov 2017, 08:13
I think this is a highquality question and I agree with explanation.



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Re D0120 [#permalink]
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10 Dec 2017, 14:18
I think this is a poorquality question. for (1), you cannot assume the set is provided in increasing order...



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Re: D0120 [#permalink]
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10 Dec 2017, 21:00



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Re: D0120 [#permalink]
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13 Mar 2018, 17:48
I got it wrong in the tests due to oversight on my part. Option 1  The factorial of a number can be odd only if its 0 or 1. This gives a value of b. But C can be any number greater than b.  Not sufficient. Option 2  c! is a prime number. The only number whose factorial is prime is 2. So we get the value of c as 2. but we do not have value of a and b. Not sufficient. Considering both the options, we can find that the numbers are consecutive numbers. Ans: C
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