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GMAT Data Analysis
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Author:  Gennadiy [ Wed Nov 14, 2012 4:30 pm ]
Post subject:  GMAT Data Analysis

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What is the median value rolled by the white die? (Note: Die is the singular of dice.)

(A) 2.5
(B) 3.0
(C) 3.5
(D) 4.0
(E) 4.5


Solution
Look at just the white bars. Since there were 20 rolls, an even number, the median will be the sum of the 2 middle values divided by 2.

1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 5, 5, 5, 6, 6, 6

Since the two values are the same, the median is 3.

The correct answer choice is (B).

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Author:  dave [ Wed Nov 14, 2012 4:44 pm ]
Post subject:  Re: GMAT Data Analysis

Can you please tell me where you got 20 rolls on the double
bar graph.

Author:  Gennadiy [ Wed Nov 14, 2012 5:02 pm ]
Post subject:  Re: GMAT Data Analysis

questioner wrote:
Can you please tell me where you got 20 rolls on the double bar graph.
The white bars represent rolls of the white die. So we disregard all the red bars and focus on the white bars only.

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Each white bar shows the quantity of outcomes with a corresponding number on the dice.
The first white bar from the left shows that "1" appeared 3 times on the rolled die.
The second white bar shows that "2" appeared 4 times on the rolled die. And so on.

All we need is to add quantities of outcomes to find the total number of rolls.
3 + 4 + 4 + 3 + 3 + 3 = 20

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