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If k is a positive integer, what is the value of k?
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03 Apr 2018, 21:58
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Re: If k is a positive integer, what is the value of k?
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03 Apr 2018, 22:18
Bunuel wrote: If k is a positive integer, what is the value of k?
(1) k is a prime number less than 5. (2) If f is any positive factor of k, then f + 1 is even. IMO E. 1) K is prime and less than 5. We have two possibilities 2 & 3. Insuff2) f is ANY positive factor of k, f + 1 is even. If f + 1 is even for all f, then f has to be always odd. There is no integer for whom all positive factors are odd as every other factor will be even! ( ex. 3*2 = 6, 3*3 = 9) Hence Insuff(1) + (2) also do not give us any new information. Hence Option (E) is our answer. Please correct me if I am wrong... gmatbusters , pushpitkc , stonecoldBest, Gladi



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Re: If k is a positive integer, what is the value of k?
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03 Apr 2018, 23:32
Gladiator59 wrote: Bunuel wrote: If k is a positive integer, what is the value of k?
(1) k is a prime number less than 5. (2) If f is any positive factor of k, then f + 1 is even. IMO E. 1) K is prime and less than 5. We have two possibilities 2 & 3. Insuff2) f is ANY positive factor of k, f + 1 is even. If f + 1 is even for all f, then f has to be always odd. There is no integer for whom all positive factors are odd as every other factor will be even! ( ex. 3*2 = 6, 3*3 = 9) Hence Insuff(1) + (2) also do not give us any new information. Hence Option (E) is our answer. Please correct me if I am wrong... gmatbusters , pushpitkc , stonecoldBest, Gladi 2. If f is any positive factor of k, then f + 1 is even If k is 3, it has two positive factors 1 and 3. If f=1, f+1 = 2 and is even If f=3, f+1 = 4 and is even This is possible for all prime numbers greater than 3 also. For example, if k=7, there are 2 positive factors 1,7 f+1 is again even for both values of f. (Insufficient)
But, when we combine the information in both the statements, the only possibility remaining is if k=3. Hence, the combined statement is enough to answer the question (Sufficient  Option C)
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Re: If k is a positive integer, what is the value of k?
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04 Apr 2018, 00:42
pushpitkc wrote: Gladiator59 wrote: Bunuel wrote: If k is a positive integer, what is the value of k?
(1) k is a prime number less than 5. (2) If f is any positive factor of k, then f + 1 is even. IMO E. 1) K is prime and less than 5. We have two possibilities 2 & 3. Insuff2) f is ANY positive factor of k, f + 1 is even. If f + 1 is even for all f, then f has to be always odd. There is no integer for whom all positive factors are odd as every other factor will be even! ( ex. 3*2 = 6, 3*3 = 9) Hence Insuff(1) + (2) also do not give us any new information. Hence Option (E) is our answer. Please correct me if I am wrong... gmatbusters , pushpitkc , stonecoldBest, Gladi 2. If f is any positive factor of k, then f + 1 is even If k is 3, it has two positive factors 1 and 3. If f=1, f+1 = 2 and is even If f=3, f+1 = 4 and is even This is possible for all prime numbers greater than 3 also. For example, if k=7, there are 2 positive factors 1,7 f+1 is again even for both values of f. (Insufficient)
But, when we combine the information in both the statements, the only possibility remaining is if k=3. Hence, the combined statement is enough to answer the question (Sufficient  Option C)Hi even k=2, factors are f=1,and 2 1+1=2 so even, k can be 2 and 3 insufficient E



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Re: If k is a positive integer, what is the value of k?
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04 Apr 2018, 00:48
kunalcvrce wrote: Hi even k=2, factors are f=1,and2
1+1=2 so even, k can be 2 and 3 insufficient E
Hey kunalcvrceHere, f=2 is a positive integer which is a factor of k=2 But f+1 is not even. Hence, we cannot use this case when combining the two statements. Thats the reason the answer is Option C!
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If k is a positive integer, what is the value of k?
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Updated on: 04 Apr 2018, 01:39
pushpitkc wrote: kunalcvrce wrote: Hi even k=2, factors are f=1,and2
1+1=2 so even, k can be 2 and 3 insufficient E
Hey kunalcvrceHere, f=2 is a positive integer which is a factor of k=2 But f+1 is not even. Hence, we cannot use this case when combining the two statements. Thats the reason the answer is Option C! hey pushpitkcin question it is mentioned If f is any positive factor of k, then f + 1 is even. any positive factor of 2 can be 1 or 2. since factor can be even after addition of one ,so k can be 2 also.
Originally posted by kunalcvrce on 04 Apr 2018, 01:02.
Last edited by kunalcvrce on 04 Apr 2018, 01:39, edited 2 times in total.



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If k is a positive integer, what is the value of k?
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04 Apr 2018, 01:03
If k is a positive integer, what is the value of k?
(1) k is a prime number less than 5. (2) If f is any positive factor of k, then f + 1 is even.
1) 2 Primes less than 5: 2,3
2) f is ANY positive factor of k, f + 1 is even. ( > f must be odd) k= f * something k= 1 * 3 = 3 k= 3 * 3 = 9
(1) + (2) We know that k=2 or k=3, f is a factor of k and f is odd. Now let f=1: k= f * something 3= 1 * 3 (or 3 * 1) 2= 1 * 2
Still two values left for k. Hence, (E)



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Re: If k is a positive integer, what is the value of k?
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05 Apr 2018, 23:05
kunalcvrce wrote: pushpitkc wrote: kunalcvrce wrote: Hi even k=2, factors are f=1,and2
1+1=2 so even, k can be 2 and 3 insufficient E
Hey kunalcvrceHere, f=2 is a positive integer which is a factor of k=2 But f+1 is not even. Hence, we cannot use this case when combining the two statements. Thats the reason the answer is Option C! hey pushpitkcin question it is mentioned If f is any positive factor of k, then f + 1 is even. any positive factor of 2 can be 1 or 2. since factor can be even after addition of one ,so k can be 2 also. Since it is mentioned any positive factor : Here any doesn't mean any one of them . Here any means on choosing any of the positive factors of 2 . as f f+1 is even Hope so your doubt is clear now.



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Re: If k is a positive integer, what is the value of k?
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06 Apr 2018, 23:22
Bunuel wrote: If k is a positive integer, what is the value of k?
(1) k is a prime number less than 5. (2) If f is any positive factor of k, then f + 1 is even. The answer should be E. Statement 1  k is a prime number less than 5. This gives us two values of k i.e. 2 and 3. Therefore not sufficient. Statement 2  If f is any positive factor of k, then f + 1 is even. Let say f = 3 and k = 6. This satisfies the condition of statement 2 i.e. \(\frac{6}{3}\) = 2 and (3+1) is even. Let's take another value for f and k. This time let both f and k be equal to 5. Now, this also satisfies statement 2 condition as \(\frac{5}{5}\) = 1 and (5+1) is even. Hence not sufficient. BOTH statement combined doesn't refines our value. As integer 1 is the factor of all integer so clearly it is a factor of 2 and 3. Additionally (1+1) = 2, which is even. Therefore both statements combined is also not sufficient. Please help me correct if I am wrong.
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