In the figure above, which of the following must equal 180?

Question

I'm bit confused about this question.

TheUltimateWinner · Answer

In this question, there is no specific indication that  1) THE LINEs are straight lines  and  2) all the LINEs go in a ONE particular POINT. 
So, without these two important information HOW can we know that the opposite angles (e.g., angle b and angle e) are equal to each other?

From the figure, I know that b+a+g+h=180
 Statement ii:  Here, I've to prove that b+e+g+h=180 or not. If I can proof that angle 'a' and angle 'e' both are equal to each other then I can say surely b+e+g+h=180.   In apparently it seems that angle 'a' and angle 'e' both are equal to each other but we've no information about...  
 1) THE LINEs are straight lines or not,
2) all the LINEs go in a particular POINT or not

Bunuel · Answer

Please check the highlighted part below.

OFFICIAL GUIDE :

Problem Solving 
 Figures:  All figures accompanying problem solving questions are intended to provide information useful in solving the problems. Figures are drawn as accurately as possible. Exceptions will be clearly noted.  Lines shown as straight are straight , and lines that appear jagged are also straight. The positions of points, angles, regions, etc., exist in the order shown, and angle measures are greater than zero. All figures lie in a plane unless otherwise indicated.

Data Sufficiency: 
 Figures: 
• Figures conform to the information given in the question, but will not necessarily conform to the additional information given in statements (1) and (2).
• Lines shown as straight are straight, and lines that appear jagged are also straight.
• The positions of points, angles, regions, etc., exist in the order shown, and angle measures are greater than zero.
• All figures lie in a plane unless otherwise indicated.

Fdambro294 · Answer

Don’t know how I dug this one up from 4 years ago, but I’ll give it a shot:

Concept tested: Vertically Opposite Angles are Equal

A = E. ——- Angle 1

B = F ———Angle 2

C = G———- Angle 3

D = H————Angle 4

A + B + C + D = 180 degree straight line for sure.

So almost like those old Chinese Menus (if we “pick 1 from column A and pick 1 from column B”):

Any combination of:

1 + 2 + 3 + 4 = 180 degrees

II and III take 1 each of the 4 different angle measures (we don’t know the exact angle measures - all we know is that vertically opposite angles are equal)

I repeats angle 1: A = E

So without further information, we don’t know if the angles in I sum to 180 degrees

II and III only
D

Posted from my mobile device

bumpbot · Answer

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In the figure above, which of the following must equal 180?

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GMAT Problem Solving (PS) Questions

In the figure above, which of the following must equal 180?

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