A certain clay cube has volume 64 cubic inches. If a smaller

Question

A certain clay cube has volume 64 cubic inches. If a smaller clay cube is formed and has half the volume of the original cube, how many inches long is an edge of the smaller cube?

A. 2
B. 4
C. 8
D.  \sqrt {4} 
E.  2 \sqrt {4}

kundankshrivastava · Accepted Answer

Volume of first cube = 64 cubic inches
Volume of Second cube = Half of First cube's volume = 64/2 = 32 cubic inches
Now volume of a cube = edge^3
hence, edge = volume^(1/3)
In this case, edge = 32^(1/3) = 2* (4)^(1/3) hence E

GMATPill · Answer

Luning,
Is this a GMAT question that you are referring to?

At GMAT Pill, we first try to set up the question.

So x*x*x = 64
x^3 = 64
So that means x = 4.

But now you're saying the volume is split in half. So the volume must now be divided by 2...how do we find the length?

So you should take 64 and split it in half to get 32. But the length still needs to be cubed to get to 32.
So use a variable y and say y^3 = 32.

You can solve for y to get your answer.

Bunuel · Answer

Theory on Geometry:
Triangles
Polygons
Circles
Coordinate geometry
3-D Geometries

3-D Geometry Questions to practice: https://gmatclub.com/forum/3-d-geometry- ... 71024.html

All DS Geometry to practice: https://gmatclub.com/forum/search.php?se ... &tag_id=32
All PS Geometry to practice: https://gmatclub.com/forum/search.php?se ... &tag_id=53

Hope this helps.

kundankshrivastava · Answer

Volume of cube A/Volume of cube B =   ^3

here Volume of Cube A = 64
Volume of Cube B = half of 64 = 32
side of cube A = 64^(1/3) = 4
side of cube B = x

putting values

(64/32) = (4/x)^3

2^(1/3) = 4/x
x = 4/2^(1/3) = 2^2/2^(1/3) = 2^(5/3) =2*2^(2/3) =2 * cubic root (4)

Hence Answer is E

shashankism · Answer

Volume of cube = 64 in^3
Volume of smaller cube = 32 in^3

So side of smaller cube =  \sqrt {32}  =  2 \sqrt {4}

Answer E

monk123 · Answer

Volume of cube = 64 
volumne of smaller cube= 64/2 = 32

side of smaller cube = ?
formulae of volume of cube = side^3
 32 = side^3
 side = 2 3√2 (2*2*2*2*2)
 
 ANSWER E

hemantbafna · Answer

Volume of cube=(side)^3

Volume of original cube= (s)^3=64

Volume of new cube= (n)^3=32.
Edge of the cube(n)=\sqrt {32}=  2 \sqrt {4}[/m

bumpbot · Answer

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A certain clay cube has volume 64 cubic inches. If a smaller

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A certain clay cube has volume 64 cubic inches. If a smaller

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