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On the number line above, the distance between any two vertical bars is constant and the distance between any two circles is also constant. Starting from zero, the vertical bars and the circles coincide at regular intervals. What is the value of D?
(1) The value of B is \(\frac{1}{12}\) units greater than the value of A.
(2) The value of B is \(50\)% smaller than the value of C.
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SolutionSteps 1 & 2: Understand Question and Draw InferencesGiven:
• Let the distance between any 2 consecutive vertical bars be x units
• Let the distance between any 2 consecutive circles by y units
• From the figure, it’s clear that \(2x = 3y - - - (I)\)
To find:
The x – coordinate of point D
• = distance between point D and 0 on the number line
o Point D has a vertical bar
o 0 has a vertical bar as well
• So, the distance between point D and 0 = Distance between 4 consecutive vertical bars
So, to answer the question, we need to find the value of x.
Step 3: Analyze Statement 1 independently(1) The x-coordinate associated with Point B is \(\frac{1}{12}\) units greater than the x-coordinate associated with Point A.
• (x- coordinate of point B) = (x – coordinate of point A) + \(\frac{1}{12}\)
o Since A and B are on the left hand side of 0, their x – coordinates will be negative
o Looking at the figure above, we can write that:
• (x- coordinate of point B) = -x
• (x – coordinate of point A) = -2y
• \(-x= -2y+\frac{1}{12}\)
• \(2y-x=\frac{1}{12}\)- - - (II)
• Equations (I) and (II) form a system of 2 linear equations having 2 unknowns.
By solving these 2 equations together, we can find a unique value of x
So statement 1 is sufficient to arrive at a unique answer.Step 4: Analyze Statement 2 independently(1) The x-coordinate associated with Point B is 50% smaller than the x-coordinate associated with Point C.
• (x- coordinate of point B) = 50% less than the (x – coordinate of point C)
o Since B and C are on the left hand side of 0, their x – coordinates will be negative
o Looking at the figure above, we can write that:
• (x- coordinate of point B) = -x
• (x – coordinate of point C) = -y
• It must be noted that in case of negative numbers, the smaller negative number will have the greater absolute value
o For example, -4 is less than -2. The absolute value of -4 is 4, which is greater than 2, the absolute value of -2
• Since 4 is 100% greater than 2, -4 will be 100% smaller than -2
o The x-coordinate of point B is smaller than the x-coordinate of point C by 50%
o So, the absolute value of the x-coordinate of point B will be greater than that of point C by 50%
• \(|-x|=(1+\frac{50}{100})|-y|\)
This equation is a restatement of Equation (I) that we’ve already deduced.
Therefore, statement 2 is not sufficient to arrive at a unique answer. Hence the correct Answer is AThanks,
Saquib
Quant Expert
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