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If a, b, c, and d are each integers greater than 1, is the product abc [#permalink]
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04 Jun 2015, 03:16
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Re: If a, b, c, and d are each integers greater than 1, is the product abc [#permalink]
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04 Jun 2015, 04:18
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Stmt 1: acd is even. No info about b. Not suff (Eg: if a =2, c=2 and d=2 acd =8; If b =6 then abcd is divisible by 6. If b =7 then abcd not divisible by 6) abd is odd. No info about c . Not suff (Eg: if a =3, b=3 and d=3 abd =27; If c =6 then abcd is divisible by 6. If b =7 then abcd not divisible by 6) Combining both: abd is odd which means a, b and d are odd. Plus Statement 1 says acd is even, so c must be even. So abcd will be even. Not sufficient to say if the product is divisible by 6. Answer E
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Re: If a, b, c, and d are each integers greater than 1, is the product abc [#permalink]
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04 Jun 2015, 04:25
Bunuel wrote: If a, b, c, and d are each integers greater than 1, is the product abcd divisible by 6?
(1) acd is even. (2) abd is odd. For product a*b*c*d to be divisible by 6 one of the four integers must be a multiple of 2 and one of them must be a multiple of 3 [Because 6 = 2 x 3]Statement 1: acd is eveni.e. One of the Numbers a, c and d is even number i.e. multiple of 2 but since we have no idea whether any number is a multiple of 3 or not therefore NOT SUFFICIENTStatement 2: abd is oddbut since we have no idea whether any number is a multiple of 3 and/or 2 or not therefore NOT SUFFICIENTCombining the two statements:One of the Numbers a, c and d is even number i.e. multiple of 2 which is Number c But even after combining the information we have no idea whether any number is a multiple of 3 or not therefore NOT SUFFICIENTAnswer: Option
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Re: If a, b, c, and d are each integers greater than 1, is the product abc [#permalink]
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04 Jun 2015, 07:47
Yes it is E. Nice question. Thank you Bunuel. Bunuel wrote: If a, b, c, and d are each integers greater than 1, is the product abcd divisible by 6?
(1) acd is even. (2) abd is odd.
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Re: If a, b, c, and d are each integers greater than 1, is the product abc [#permalink]
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04 Jun 2015, 18:59
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If a, b, c, and d are each integers greater than 1, is the product abcd divisible by 6?
is abcd by 2*3 ?
(1) acd is even. a=2 c=7 d=3 yes, divisible
a=2 c=7 d=1 no, not divisible Insufficient
(2) abd is odd. a=11 b=11 d=11 and c=6 yes divisible
a=11 b=11 d=11 and c = 2 not divisible Insufficient
Combined, We still are uncertain if its divisible or not, a,b,d=11 c=6 or 2 Answer: E



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Re: If a, b, c, and d are each integers greater than 1, is the product abc [#permalink]
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05 Jun 2015, 08:59
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stmt 1  we get acd is even so one of them/two of them or all of them can be even and no info about b so not sufficient. stmt 2  abd is odd  so all of them are odd but no info about c  not sufficient combining  we get a d b are odd and c is even, for the product to be divisible by 6 it should be divisible by 2 and 3 with c being even it is divisible by 2 but we are not sure about the other odd numbers, for they can be 13,17,19 or 3 9 15.
hence ans E



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If a, b, c, and d are each integers greater than 1, is the product abc [#permalink]
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05 Jun 2015, 19:04
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Q If a, b, c, and d are each integers greater than 1, is the product abcd divisible by 6? in other words does abcd have factors of 2, 3 stmt (1) acd is even. atleast one integer is 2 or factor of 2 ; no info about 3 as a factor.  Not Sufficient
stmt (2) abd is odd one integer out of (abd) can be factor of 3 or none (abd) factor of 3; no info about 2 as a factor.  Not Sufficient (a b d) ~ 5 * 7 * 11 (a b d) ~ 3 * 5 * 7
together stmt (1) & (2) , same as above : 2* 5 * 7 * 11 = no 2* 3 * 5 * 7 = yes  Not Sufficient
Ans : E
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Re: If a, b, c, and d are each integers greater than 1, is the product abc [#permalink]
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08 Jun 2015, 03:12
Bunuel wrote: If a, b, c, and d are each integers greater than 1, is the product abcd divisible by 6?
(1) acd is even. (2) abd is odd. MANHATTAN GMAT OFFICIAL SOLUTION:Another way of saying that an integer is divisible by 6 is to say that it is a multiple of 6. Multiples of 6 must have all of the prime factors of 6 (6 = 2 × 3) and could have additional prime factors. Thus, our rephrased question is “Does the product abcd have at least one 2 and one 3 as prime factors?” (1) INSUFFICIENT: This tells us that at least one of the integers a, c, and d must be even. Thus we have at least one 2 as a prime factor. However, we do not know anything about the remaining factors, and cannot determine whether there is one 3 among the prime factors of a, b, c, and d. (2) INSUFFICIENT: This tells us that a, b, and d are all odd, which means there is no factor of 2 among their prime factors. Without information about c, we are uncertain about whether abcd has a factor of 2. Additionally, we have no information about the number of 3s among the prime factors of a, b, and d. It is possible that abd is 105, for example, and we would have the 3 required for divisibility by 6. On the other hand, abd could be 125 and we would have no 3s as factors. (1) AND (2) INSUFFICIENT: If acd is even and if abd is odd, it must be true that c is even and that abcd has at least one factor of 2. Neither of the statements gives us a conclusive answer about the number of 3s among the prime factors of a, b, c, and d, however, and combining the statements does nothing to resolve that uncertainty. The correct answer is E.
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Re: If a, b, c, and d are each integers greater than 1, is the product abc [#permalink]
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26 Jun 2015, 19:45
Hello
I think official solution is flawed since it consider 125 in explaining statement 2.
It is mentioned as a b c d so we presume that these integers are distinct. Please correct me if I am wrong.



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Re: If a, b, c, and d are each integers greater than 1, is the product abc [#permalink]
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27 Jun 2015, 02:33



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Re: If a, b, c, and d are each integers greater than 1, is the product abc [#permalink]
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25 Sep 2017, 17:39
Bunuel wrote: If a, b, c, and d are each integers greater than 1, is the product abcd divisible by 6?
(1) acd is even. (2) abd is odd. Statement 1 Too many possibilities insuff Statement 2 This just tells us abd are all odd integers...no info about what integers they are insuff Statement 1 & 2 5 * 7 * 11 * some even integers 3* 5 * 11 * some even integer If there were a restriction that one of the integers had to be 3 then both would be suff but otherwise insuff




Re: If a, b, c, and d are each integers greater than 1, is the product abc
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