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Set A consists of all distinct prime numbers which are 2 mor
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17 Feb 2014, 03:54
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Set A consists of all distinct prime numbers which are 2 more than a multiple of 3. If set B consists of distinct integers, is set B a subset of set A? (1) Set B consist of two positive integers whose product is 10. (2) The product of reciprocals of all elements in set B is a terminating decimal
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Re: Set A consists of all distinct prime numbers which are 2 mor
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17 Feb 2014, 03:54
SOLUTIONSet A consists of all distinct prime numbers which are 2 more than a multiple of 3. If set B consists of distinct integers, is set B a subset of set A?According to the definition set A = {2, 5, 11, 17, 23, 29, 41, ...} (1) Set B consist of two positive integers whose product is 10. 10 can be broken into the product of two integers in two ways: 10 = 1*10 and 10 = 2*5. If set B = {1, 10}, then the answer to the question is NO but if set B = {2, 5}, then the answer to the question is YES. Not sufficient. (2) The product of reciprocals of all elements in set B is a terminating decimal. If set B = {4, 8}, then the answer to the question is NO but if set B = {2, 5}, then the answer to the question is YES. Not sufficient. (1)+(2) Both possible sets from (1) meet the condition stated in the second statement: \(\frac{1}{1}*\frac{1}{10}=\frac{1}{10}=0.1= terminating \ decimal\) and \(\frac{1}{2}*\frac{1}{5}=\frac{1}{10}=0.1= terminating \ decimal\). Thus we still have two sets, which give two different answers to the question. Not sufficient. Answer: E.
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Re: Set A consists of all distinct prime numbers which are 2 mor
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17 Feb 2014, 04:19
Bunuel wrote: Set A consists of all distinct prime numbers which are 2 more than a multiple of 3. If set B consists of distinct integers, is set B a subset of set A?
(1) Set B consist of two positive integers whose product is 10. (2) The product of reciprocals of all elements in set B is a terminating decimal Sol: Possible values of Set A ={5,11,17,23,29,41,47...} St 1: Possible combination with multiple of 10 ( 1,10) (2,5) > Clearly not a subset of A So sufficient St 2: Since the reciprocal is a terminating decimal so the terms will be of of 1/ (2^a*5^b) where a and b are integers So possible value are {2,5,10, 20,125.....} If Set B has only 1 element let us say {5} then B is subset otherwise not Ans is A
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Re: Set A consists of all distinct prime numbers which are 2 mor
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17 Feb 2014, 04:23
WoundedTiger wrote: Bunuel wrote: Set A consists of all distinct prime numbers which are 2 more than a multiple of 3. If set B consists of distinct integers, is set B a subset of set A?
(1) Set B consist of two positive integers whose product is 10. (2) The product of reciprocals of all elements in set B is a terminating decimal Sol: Possible values of Set A ={5,11,17,23,29,41,47...}St 1: Possible combination with multiple of 10 ( 1,10) (2,5) > Clearly not a subset of A So sufficient St 2: Since the reciprocal is a terminating decimal so the terms will be of of 1/ (2^a*5^b) where a and b are integers So possible value are {2,5,10, 20,125.....} If Set B has only 1 element let us say {5} then B is subset otherwise not Ans is A Like many GMAT Club's questions, this one is tricky... Set A is missing an important element.
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Re: Set A consists of all distinct prime numbers which are 2 mor
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17 Feb 2014, 04:47
Bunuel wrote: WoundedTiger wrote: Bunuel wrote: Set A consists of all distinct prime numbers which are 2 more than a multiple of 3. If set B consists of distinct integers, is set B a subset of set A?
(1) Set B consist of two positive integers whose product is 10. (2) The product of reciprocals of all elements in set B is a terminating decimal Sol: Possible values of Set A ={5,11,17,23,29,41,47...}St 1: Possible combination with multiple of 10 ( 1,10) (2,5) > Clearly not a subset of A So sufficient St 2: Since the reciprocal is a terminating decimal so the terms will be of of 1/ (2^a*5^b) where a and b are integers So possible value are {2,5,10, 20,125.....} If Set B has only 1 element let us say {5} then B is subset otherwise not Ans is A Like many GMAT Club's questions, this one is tricky... Set A is missing an important element. Yes it is. Possible values in Set A ={ 2,5,11,17,23,29,41....} So if Set B={2,5} then yes but Set B={1,10} then No So A and D ruled out St2 : If Set B {2},{5} or {10} or {2,5} then yes otherwise no. So St 2 is ruled out Combining we get Set B ={ 2,5} Ans C
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Re: Set A consists of all distinct prime numbers which are 2 mor
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23 Feb 2014, 06:01
really tricky one ! Let set B = {2,5} then yes , B is a subset of of A let B = {1,10} Then no, B is not a subset of A Answer E.
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Re: Set A consists of all distinct prime numbers which are 2 mor
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23 Feb 2014, 06:05
SOLUTIONSet A consists of all distinct prime numbers which are 2 more than a multiple of 3. If set B consists of distinct integers, is set B a subset of set A?According to the definition set A = {2, 5, 11, 17, 23, 29, 41, ...} (1) Set B consist of two positive integers whose product is 10. 10 can be broken into the product of two integers in two ways: 10 = 1*10 and 10 = 2*5. If set B = {1, 10}, then the answer to the question is NO but if set B = {2, 5}, then the answer to the question is YES. Not sufficient. (2) The product of reciprocals of all elements in set B is a terminating decimal. If set B = {4, 8}, then the answer to the question is NO but if set B = {2, 5}, then the answer to the question is YES. Not sufficient. (1)+(2) Both possible sets from (1) meet the condition stated in the second statement: \(\frac{1}{1}*\frac{1}{10}=\frac{1}{10}=0.1= terminating \ decimal\) and \(\frac{1}{2}*\frac{1}{5}=\frac{1}{10}=0.1= terminating \ decimal\). Thus we still have two sets, which give two different answers to the question. Not sufficient. Answer: E.
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Re: Set A consists of all distinct prime numbers which are 2 mor
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22 Sep 2017, 10:16
Bunuel wrote: SOLUTION
Set A consists of all distinct prime numbers which are 2 more than a multiple of 3. If set B consists of distinct integers, is set B a subset of set A?
According to the definition set A = {2, 5, 11, 17, 23, 29, 41, ...}
(1) Set B consist of two positive integers whose product is 10. 10 can be broken into the product of two integers in two ways: 10 = 1*10 and 10 = 2*5. If set B = {1, 10}, then the answer to the question is NO but if set B = {2, 5}, then the answer to the question is YES. Not sufficient.
(2) The product of reciprocals of all elements in set B is a terminating decimal. If set B = {4, 8}, then the answer to the question is NO but if set B = {2, 5}, then the answer to the question is YES. Not sufficient.
(1)+(2) Both possible sets from (1) meet the condition stated in the second statement: \(\frac{1}{1}*\frac{1}{10}=\frac{1}{10}=0.1= terminating \ decimal\) and \(\frac{1}{2}*\frac{1}{5}=\frac{1}{10}=0.1= terminating \ decimal\). Thus we still have two sets, which give two different answers to the question. Not sufficient.
Answer: E. Hi Bunuel How will we get 2 in set A? can u pls explain.. As per my understanding, 2 more than a multiple of 3 means..It starts with {5,11,17...} Pls help



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Re: Set A consists of all distinct prime numbers which are 2 mor
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22 Sep 2017, 10:22
zanaik89 wrote: Bunuel wrote: SOLUTION
Set A consists of all distinct prime numbers which are 2 more than a multiple of 3. If set B consists of distinct integers, is set B a subset of set A?
According to the definition set A = {2, 5, 11, 17, 23, 29, 41, ...}
(1) Set B consist of two positive integers whose product is 10. 10 can be broken into the product of two integers in two ways: 10 = 1*10 and 10 = 2*5. If set B = {1, 10}, then the answer to the question is NO but if set B = {2, 5}, then the answer to the question is YES. Not sufficient.
(2) The product of reciprocals of all elements in set B is a terminating decimal. If set B = {4, 8}, then the answer to the question is NO but if set B = {2, 5}, then the answer to the question is YES. Not sufficient.
(1)+(2) Both possible sets from (1) meet the condition stated in the second statement: \(\frac{1}{1}*\frac{1}{10}=\frac{1}{10}=0.1= terminating \ decimal\) and \(\frac{1}{2}*\frac{1}{5}=\frac{1}{10}=0.1= terminating \ decimal\). Thus we still have two sets, which give two different answers to the question. Not sufficient.
Answer: E. Hi Bunuel How will we get 2 in set A? can u pls explain.. As per my understanding, 2 more than a multiple of 3 means..It starts with {5,11,17...} Pls help 0 is a multiple of 3 (0 is a multiple of every positive integer) so 2 is 2 more than a multiple of 3.
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Re: Set A consists of all distinct prime numbers which are 2 mor
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09 Dec 2018, 05:33
Hi! Sorry but how do you know from statement 2 that set B has only 2 values? Is it because of the reciprocity given in the question stem?



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Set A consists of all distinct prime numbers which are 2 mor
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26 May 2019, 14:05
lukevol123 we don't know that it only has two. It's just a simple example picking numbers to see a pattern. Given: {A} is pn = 3q+2 so multiples of 3 + 2 that are prime... so A is {2, 5, 11 ...} {B} = some nonrepeating amount of ints Question: are all ints in {B} in {A}? (1) Set B consist of two positive integers whose product is 10.10 = 1*10 or 2*5 If B is {1,10} ... NO If B is {2,5} ... YES Insufficient. (2) The product of reciprocals of all elements in set B is a terminating decimalIf it's a terminating decimal then the reciprocals of the ints have to only have 2s, 5s or 10s. If B is {1,10} then it's 1/1 * 1/10 = 1/10, a terminating decimal... NO If B is {2,5} then it's 1/2 * 1/5 = 1/10, a terminating decimal... YES (3) Combining both doesn't add any new information.



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Re: Set A consists of all distinct prime numbers which are 2 mor
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28 Jul 2019, 07:38
Asked vide a PM : Why are we skipping prime numbers 7 and 19 , what does this line actually mean, Set A consists of all distinct prime numbers which are 2 more than a multiple of 3" Response: it means we need to consider all numbers in the form of N= 3n+2 , which are prime. putting n = 0,1,2,3,4..., we get N = 2,5,8,11,14,17... Now we need to select the numbers which are prime. So the Set A = {2,5,11,17...}
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Re: Set A consists of all distinct prime numbers which are 2 mor
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