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Re: The Ultimate Q51 Guide [Expert Level] [#permalink]
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05 Sep 2016, 16:49
NandishSS wrote: MathRevolution wrote: This is a 5051 level question
(ex 7) *(integer) What is the greatest common divisor of positive integers n and m? 1) n=1 2) m=n+1 There are 2 variables in the original condition (m, n). In order to match the number of variables and the number of equations, we need 2 equations. Hence, there is a high chance that C is the correct answer. Using 1) and 2), C is the correct answer. However, we have to utilize the common mistake type 4(B) since it is an integer question. The correct answer is D. MathRevolution Could pls elaborate this que how the ans is D 1) if a certain number is 1, the greatest common divisor is always 1 2) in case of consecutive numbers, the greatest common divisor is also 1. Hence, the conditions are sufficient, and the correct answer is D.
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Re: The Ultimate Q51 Guide [Expert Level] [#permalink]
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06 Sep 2016, 09:14
Jin,
Most of the tough questions i got today were from coordinate geometry. Surprisingly the question pool threw no questions such divisbility etc. The geometry questions on GMAT were much more tougher than we see on any prep material.



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07 Sep 2016, 21:47
Below is a 5051 level questions. It involves ignoring square in inequality. If p^4q^7r^5<0, is pqr<0? 1) q>0 2) r<0 If we modify the original condition and the question, we If qr<0, is pqr<0? and p>0? However, since we do not have data for p, the correct answer is E.
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Re: The Ultimate Q51 Guide [Expert Level] [#permalink]
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09 Sep 2016, 16:23
Below is CMT4 quesiton When p and t are positive integers and p is a factor of t, is t/p an even? 1) t is an even 2) p+t is an odd There are 2 variables in the original condition, hence, there is a high chance that C is the correct answer. Using 1) & 2), C is the correct answer. However, since this is a key question, if we apply CMT 4(A), using condition 2), the answer becomes yes and the condition is sufficient. Thus, the correct answer is B.
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Re: The Ultimate Q51 Guide [Expert Level] [#permalink]
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10 Sep 2016, 06:20
Senthil7 wrote: Jin,
Most of the tough questions i got today were from coordinate geometry. Surprisingly the question pool threw no questions such divisbility etc. The geometry questions on GMAT were much more tougher than we see on any prep material. Hi Senthil 7, In fact, coordinate geometry questions given are not that difficult. The distance between two spots, areas of triangles, squares, parallelograms, questions to solve with the mistake type 4(A) of DS are given. It may seem difficult when you actually draw, but it is not that difficult. Best regards, Jin Math Revolution
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Re: The Ultimate Q51 Guide [Expert Level] [#permalink]
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10 Sep 2016, 20:47
If 5digit positive integer ab,aba is divided by 3, what is the remainder? 1) a=3 2) b=1 We can modify the original condition and the question. If we divide ab and abc by 3, the remainder is same as a+b+a+b+a=3a+2b divided 3. Hence, since 3a is same as 3, we only have to know 2b. Thus, the correct answer is B.
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Re: The Ultimate Q51 Guide [Expert Level] [#permalink]
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11 Sep 2016, 17:45
There are some 5051 level geometry questions. A triangle has 3 sides x, y, z such that x<y<z. Is this a right triangle? 1) x^2+y^2=4^2+5^2 2) y^2+z^2=5^2+(√41)^2 There are 3 variables (x,y,z) in the original condition. Hence, the correct answer is E. Using con 1) and 2), we get the answer as yes when (x,y,z)=(4,5,√41) and the answer as no when (x,y,z)=(3, √32, √34).
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Re: The Ultimate Q51 Guide [Expert Level] [#permalink]
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12 Sep 2016, 16:02
Below is 5051 level question The product of the units digit, tens digit, and hundreds digit of a positive 3digit integer n less than 500 is 15, what is the value of n? 1) n>350 2) The sum of the units digit, tens digit, and hundreds digit of a positive 3digit integer n is 8. There are 3 variables in the original condition and 1 equation. Hence, there is a high chance that C is the correct answer. Since this is a key question, one of integer questions, we need to apply the CMT 4(A). Hence, using con 1), we get n=351. The condition is sufficient and the correct answer is A.
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Re: The Ultimate Q51 Guide [Expert Level] [#permalink]
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14 Sep 2016, 01:40
Is x1>x+3? 1) x<1 2) x<1 If we modifiy the original condition and the question, we should square both sides. Then we get x^22x+1>x^2+6x+9? ==> 2x+1>6x+9?, x<1?. Hence the correct answer is A.
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Re: The Ultimate Q51 Guide [Expert Level] [#permalink]
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14 Sep 2016, 02:22
could you please solve this question?
There are five homes. If the median price of a home is $200,000, is the range of all prices greater than $80,000? 1) The average price of the five homes is $240,000. 2) Three of five homes have the same price.



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Re: The Ultimate Q51 Guide [Expert Level] [#permalink]
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14 Sep 2016, 02:28
and this one too please
If r>s, is r>s? 1) r>0 2) s>0



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Re: The Ultimate Q51 Guide [Expert Level] [#permalink]
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14 Sep 2016, 03:04
Answer is D, both statements are individually enough Sent from my iPhone using GMAT Club Forum mobile app



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Re: The Ultimate Q51 Guide [Expert Level] [#permalink]
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22 Sep 2016, 15:51
As always, questions like CMT 3,4 are often on the exam in a more developed form. Take a look at below and you’ll see the type of question that’s really common these days. This one, too, is a 5051evel problem that is equivalent to CMT 4(A). You must get used to these. You need to know how variable approaches and CMT are related. (ex 1) (integer) If x and y are postive integers, what is the remainder when 100x+y is divided by 11? 1) x=22 2) y=1 ==> If you change the original condition and the prolem, you all ways get the remainder of 1 if you divide 100x by 11 regardless of the value of x. Thus, you only need to know y. Therefore, the answer is . This is a typical 5051 level problem. (CMT 4(A)) Answer: A
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Re: The Ultimate Q51 Guide [Expert Level] [#permalink]
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22 Sep 2016, 16:06
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MathRevolution wrote: If you change the original condition and the prolem, you all ways get the remainder of 1 if you divide 100x by 11 regardless of the value of x. Thus, you only need to know y. Therefore, the answer is . This is a typical 5051 level problem. (CMT 4(A)) Answer: A
Your answer is wrong. If x = 0, the remainder in the division of 100x by 11 is 0, and if x = 3, the remainder is 3. Not the first time you've posted a wrong solution in this thread though. Posted from my mobile device
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24 Sep 2016, 05:03
2) The question below is a 5051level problem, and an inequality problem that ignores squared numbers (ex 2) (inequality) If x and y are positive, is y/x > x/y? 1) y>x 2) y=x+2 ==> If you change the original condition and the problem, since x and y are positive numbers, the sign of inequality does not change even if both sides are multiplied by xy. If so, in y/x>x/y?, y2x2>0?, (yx)(y+x)>0?, y+x>0, thus, yx>0?, y>x?. In the case of 1) the answer is yes, and in the case of 2) yx=2>0 yes, thus the answer is D. Answer: D
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26 Sep 2016, 04:20
3) Let’s always be careful about the CMT 4(A) like the one below (ex 3) (statistics) What is the standard deviation of 10 numbers? 1) The standard deviation of them is d, then d2d=0 2) The product of all the 10 numbers is negative ==> In the original condition, the answer is highly likely to be E with 10 variables. If you go with 1) & 2) you get, from d(d1)=0, you get d=0,1, and in the case of 2) in order for the mulplication of ten numbers to get negative number, there has to be at least one number that is different from each other. Thus, d≠0, and d=1, hence suffi. Therefore, the answer is C. Answer: C
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Re: The Ultimate Q51 Guide [Expert Level] [#permalink]
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27 Sep 2016, 07:47
If a and b are integers, is ab+1 an odd? 1) a is an even 2) b is an odd ==> In the original condition, C is likely to be the answer since there are 2 variables (a,b). If you solve 1) & 2), you actually get C as an answer. However, this problem, too, is a integer problem(a key question), and if you apply CMT 4(A), if you do 1), a=even, it becomes ab=even ab+1=even+1=odd, hence yes, and suffi. Therefore, the answer is A. Answer: A
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27 Sep 2016, 07:48
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MathRevolution wrote: Below is 5051 level question The product of the units digit, tens digit, and hundreds digit of a positive 3digit integer n less than 500 is 15, what is the value of n? 1) n>350 2) The sum of the units digit, tens digit, and hundreds digit of a positive 3digit integer n is 8. There are 3 variables in the original condition and 1 equation. Hence, there is a high chance that C is the correct answer. Since this is a key question, one of integer questions, we need to apply the CMT 4(A). Hence, using con 1), we get n=351. The condition is sufficient and the correct answer is A. Wait hold on. If the 3 digits are 1, 3, and 5, how is it possible that their sum is 8? This is a terribly written question.
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Re: The Ultimate Q51 Guide [Expert Level] [#permalink]
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29 Sep 2016, 05:12
CMT 4(B) still often comes out these days. If a and b are prime numbers, what is the value of a+b? 1) 30≤a<b≤40 2) ab=1,147 ==>In the original condition, the answer is highly likely to be C since there are 2 variables (a,b). If you do 1)&2), in the case of 1), you get a=31, b=37, hence unique, and suffi. In the case of 2),too, it becomes 31*37=1,147, therefore suffi. The answer is D. You must not forget about CMT 4(B) like this one with 1) easy and 2) difficult. If you can do A, B easily, consider D. Hence the answer is D. Answer: D
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Re: The Ultimate Q51 Guide [Expert Level] [#permalink]
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30 Sep 2016, 06:24
If x≠0, is x^2/x<1? 1) 1<x<1 2) 0<x ==>If you change the original condition and the problem, you get is x^2/x<1? > is x^2/x<1? > is x<1? > 1<x<1?, so A is the answer. Answer: A
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