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A, B, C, and D are points on a line. If C is the midpoint of line segm
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15 Jun 2016, 02:20
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A, B, C, and D are points on a line. If C is the midpoint of line segment AB and if D is the midpoint of line segment CB, is the length of line segment DB greater than 5? 1) The length of line segment AC is greater than 8 2) The length of line segment CD is greater than 6
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Re: A, B, C, and D are points on a line. If C is the midpoint of line segm
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15 Jun 2016, 05:14
AbdurRakib wrote: A, B, C, and D are points on a line. If C is the midpoint of line segment AB and if D is the midpoint of line segment CB, is the length of line segment DB greater than 5?
1) The length of line segment AC is greater than 8 2) The length of line segment CD is greater than 6 so from the given info....AB is teh line..... C is the midpoint.....\(AC = BC = \frac{AB}{2}.....\) D is the midpoint of CB..............\(CD = BD = \frac{BC}{2} = \frac{AB}{4}..\) lets see the statements 1) The length of line segment AC is greater than 8 \(BD = \frac{BC}{2} = \frac{AC}{2}\) ..... so if AC>6, DB > 3..... DB can be 4, 5 ,6 etc Insuff 2) The length of line segment CD is greater than 6\(BD = CD.\).. so if CD >6, BD>6.. Suff B
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Re: A, B, C, and D are points on a line. If C is the midpoint of line segm
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06 Dec 2016, 07:21
AbdurRakib wrote: A, B, C, and D are points on a line. If C is the midpoint of line segment AB and if D is the midpoint of line segment CB, is the length of line segment DB greater than 5?
1) The length of line segment AC is greater than 8 2) The length of line segment CD is greater than 6 We are given that A, B, C, D are points on a line. We also also given that C is the midpoint of line segment AB and D is the midpoint of line segment CB. We need to determine whether the length of line segment DB is greater than 5. Let’s denote the length of a line segment using the absolute value sign. Therefore, the question becomes: Is DB > 5? Since C is the midpoint of line segment AB, C must be between A and B. Furthermore, since D is the midpoint of line segment CB, D must be between C and B. Therefore, the points lie on the line in the following order: A, C, D, B. Since D is the midpoint of line segment CB, we have CD = DB. Notice that CB = CD + DB. Since CD = DB, that means CB = 2DB. Moreover, since C is the midpoint of line segment AB, AC = CB. Since CB = 2DB, AC = 2DB. Statement One Alone:The length of line segment AC is greater than 8. Since we know AC = 2DB, we know that 2DB > 8 and thusDB > 4 However, knowing DB is greater than 4 does not mean it is greater than 5. Statement one alone is not sufficient to answer the question. We can eliminate answer choices A and D. Statement Two Alone:The length of line segment CD is greater than 6. Recall that CD = DB. Therefore, if CD > 6, then DB > 6 and thus DB > 5. Statement two alone is sufficient to answer the question. Answer: B
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Re: A, B, C, and D are points on a line. If C is the midpoint of line segm
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12 Dec 2017, 10:36
Hi All, We're told that A, B, C, and D are points on a line, C is the midpoint of line segment AB and D is the midpoint of line segment CB. We're asked if the length of line segment DB is greater than 5. This is a YES/NO question. You might find it useful to draw a picture (and it would likely help you to make the algebraic 'deductions' that are needed to answer this question). <   A      C   D   B   > In the above example, C is the midpoint of AB and D is the midpoint of CB, so... AC = CB = X CD = DB = Y X = 2Y The question essentially asks if Y is greater than 5. 1) The length of line segment AC is greater than 8 With Fact 1, we know that X is greater than 8. This means that Y is greater than 4. IF... Y = 6, then the answer to the question is YES. IF... Y = 5, then the answer to the question is NO. Fact 1 is INSUFFICIENT 2) The length of line segment CD is greater than 6 With Fact 2, we know that Y is greater than 6. Thus, the answer to the question is ALWAYS YES. Fact 2 is SUFFICIENT Final Answer: GMAT assassins aren't born, they're made, Rich
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Re: A, B, C, and D are points on a line. If C is the midpoint of line segm
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13 Apr 2020, 06:15
AbdurRakib wrote: A, B, C, and D are points on a line. If C is the midpoint of line segment AB and if D is the midpoint of line segment CB, is the length of line segment DB greater than 5?
1) The length of line segment AC is greater than 8 2) The length of line segment CD is greater than 6 Given: A, B, C, and D are points on a line. If C is the midpoint of line segment AB and if D is the midpoint of line segment CB When we sketch this information we get the following: Notice that the two blue bars of equal length represent AC = CB, and the two red bars of equal length represent CD = DB. Aside: The 4 points could also be arranged as B..D..C......A, but that doesn't change the answer to the questionTarget question: Is the length of line segment DB greater than 5? Statement 1: The length of line segment AC is greater than 8 There are several scenarios that satisfy statement 1. Here are two: Case a: AC = 9. In this case, the answer to the target question is NO, line segment DB is NOT greater than 5Case b: AC = 14. In this case, the answer to the target question is YES, line segment DB IS greater than 5Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT Statement 2: The length of line segment CD is greater than 6Since CD = DB, we can conclude that line segment DB IS greater than 6, which means line segment DB IS greater than 5Since we can answer the target question with certainty, statement 2 is SUFFICIENT Answer: B Cheers, Brent
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Re: A, B, C, and D are points on a line. If C is the midpoint of line segm
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