Which of the following equations is sufficient to determine

Question

https://gmatclub.com/forum/download/file.php?mode=view&id=40842 Which of the following equations is sufficient to determine which of the five distinct integers represented on the number line above is closest to zero, given that the distance between every two adjacent integers is not shown to scale? A. b + d = 2c B. d = ‒a C. c < ‒e D. b = ‒d E. a + b = ‒d ‒ e GST Week 1 Day 5 Exampal Question 1 Give your best shot at writing a top notch application and you will have the chance to win GMAT Club tests daily and Exampal Premium GMAT Package. See the GMAT Spring Training Thread for all details Screen Shot 2018-04-14 at 7.18.06 PM.png

souvonik2k · Answer

Hi  souvik101990 
I think we are missing 'equal to' signs here. Correct me if I am wrong. Question should go like this:
A. b + d = 2c ---c is average of b and d. No info on no. closest to zero.
B. d = ‒a --- b or c can be closest so not sure.
C. c < ‒e -----Either d or e could be closest to zero. Not sufficient.
D. b = ‒d ----Only c can be closest to zero. Sufficient.
E. a + b = ‒d ‒ e ----Cannot determine since only sum is equal.

Answer D.

souvik101990 · Answer

Thank you,  souvonik2k , I fixed it.

Sayon · Answer

A. b + d = 2c : Just says c is mid point of b and d. Any value can be closer to zero.

B. d = ‒a : Says a and d are equidistant from 0. But we still cannot be sure which among b,c is closer to zero.

C. c < ‒e : any of d,e can be closer

D. b = ‒d : b and d are equidistant from zero and c can be any value between b and d, which makes it closest to zero. -ANSWER

E. a + b = ‒d ‒ e : any of b,c,d can be closest to zero.

Answer-D

pawanpoolla · Answer

The answer is Option D . This is similar to a data sufficiency question of the type "Is X ..." . However, isn't very difficult to solve using POE. A. Let's assume all the integers to be positive (b,d,c =2,5,8) - then "a" must be closest to 0. Now flip the assumption, all the integers are negative (b,d,c =-8,-5,-2) - then "e" must be closest to 0. Hence no clear answer. Reject B. "d=-a" implies that 0 lies between the two. It could be ab or bc or cd - so we can't be sure of which is closest to 0. Reject C. This is a little interesting. So either e>-e or -e>e (if e is negative). If -e>e, then 0 lies between them and hence closest to e. However, if e>-e , -e may lie between de or cd. . So 0 will also be between de or cd. No clear answer here. Reject E. Let's assume e>0 and a,b,c,d<0, then the equation may hold true for a high value of e and 0 will be close to "d". Now let's flip this, a<0 and b,c,d,e>0. Then 0 will be closer to "b". Since no clear answer - Reject D. b=-d so 0 lies between them. Now since 0 is equidistant from both b and d, it can't be closer to either one of them. Hence closest is c. Since we have a conclusive answer - Accept

souvik101990 · Answer

souvonik2k  - Congrats on nailing it. PM me to get your reward!

ScottTargetTestPrep · Answer

Solution:

We need to establish a relationship such that one of the integers is positive and one is negative; in this way, we will have an interval that includes 0 in it. Choices B and D are the most promising ones, as in both choices one of the integers is positive and the other one is negative. However, we can easily eliminate answer choice B as there are two integers between a and d (which are b and c). Since the number line is not drawn to scale, it is impossible for us to determine which one of b or c is closer to 0. Thus, let’s analyze answer choice D in greater detail.

Since b = -d, we see that d must be positive and b must be its opposite. So b and d are equidistant from 0. However, since c is somewhere between b and d, then c is even closer to 0 than either b or d (despite the fact that the distance between the two adjacent integers is not drawn to scale). Therefore, c is closest to 0 if we know b = -d.

Answer: D

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Which of the following equations is sufficient to determine

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Which of the following equations is sufficient to determine

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