Confusing Rectangular Box?

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Confusing Rectangular Box?

by oquiella » Sun Sep 27, 2015 6:56 pm
A rectangular box is 10 inches wide, 10 inches long, and 5 inches high. What is the greatest possible (straight-line) distance, in inches, between any two points on the box?

A. 15
B. 20
C. 25
D. 10 Square root 2
E. 10 Square root 3

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by Bullzi » Sun Sep 27, 2015 7:26 pm
Hello,
This is how I could approach, I'll let the experts confirm if this approach is right..

It looks like the question asks us to find the diagonal of a rectangular cube. Ill use the equation to find the diagonal,
d2 = l2 + w2 + h2
where d, l, w and h are diagonal, length width and height. Substituting values, we have

d2 = (10*10)+(10*10)+(5*5) which gives [spoiler]d = 5[/spoiler]. So, I'll go with Option A

Thanks
Bullzi

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by Brent@GMATPrepNow » Sun Sep 27, 2015 7:51 pm
Here's a related video that explains the related formula: https://www.gmatprepnow.com/module/gmat- ... /video/869
Brent Hanneson - Creator of GMATPrepNow.com
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