If the volume of cube A is twice that of cube B, the side of

Question

If the volume of cube A is twice that of cube B, the side of cube A is how many time that of cube B?

A. 1/2
B.  \sqrt {2} 
C.  3\sqrt {2} 
D. 2
E. 8

sumande · Answer

side of cube A = a
side of cube B = b

a^3 = 2 * b^3
a = cubed rt(2) * b

Hence, B.

jimmyjamesdonkey · Answer

B is correct, incorrect approach to solve.

jimmyjamesdonkey · Answer

Nevermind - misread your answer. You got it.

ashkrs · Answer

B : This looked like a plain vanilla. Was there any trick involved??

ywilfred · Answer

Let side of cube A be x, side of cube B be y

Volume of A = x^3
Volue of B = y^3

x^3 = 2y^3
x = 2^1/3(y)

So the side of A is cube root (2) of B

KillerSquirrel · Answer

ywilfred is correct:

X = one cube
Y = second cube

x^3 = y^3*2 ---> (one volume is twice the other volume)

3sqrt(2)^3 = 2

x^3 = y^3*3sqrt(2)^3

x^3 = (y*3sqrt(2))^3 ---> the same way that 2^2*3^2 = 6^2

x = y*3sqrt(2)

the answer is (B) = cubed rt(2) = 3sqrt(2)

:-D

kundankshrivastava · Answer

Volume of cube is directly proportional to the cube of side
Volume of CubeA/Volume of Cube B =  ^3

in this question
Volume of A/Volume of B = 2

^3 = 2

Side of cube A/side of cube B = cubic root (2)

Side of cube A = cubic root (2) * Side of B

Hence Answer is B

Bunuel · Answer

3-D Geometry Questions Directory: 3-d-geometry-questions-171024.html

Temurkhon · Answer

any cubes are similar each other meaning that the ratio of theirs volumes is third degree of their side's ratio, so

a^3/2b^3=sqrt^3 of a^3/sqrt^3 of (2b)^3=a/ sqrt^3 of 2 *b

B

PareshGmat · Answer

Let volume of cube B = 1 = 1 * 1 *1

Then volume of cube A = 2  = 2^{\frac{1}{3}} * 2^{\frac{1}{3}} * 2^{\frac{1}{3}}

Dimension of Cube A is  2^{\frac{1}{3}}  times that of dimension of cube B

Answer = B

kanusha · Answer

Concept is Cube
Cube _ 6 Sides , Volume is S^3 , Given 2 Cubes
S^3 = 2 x S^3
???Confused
Changing the variables as two Different Cubes
a^3 = 2 b^3 ( A is twice that of B)
a = ? ??
a x a^2 = 2 x b^3
a = 2 x b^3 /a^2 ?????
Next? :idea:

?

Is my thought process is right??

? Is my thought process is right??

PareshGmat · Answer

Instead of taking 2 variables, just try plugins... Please look at posts above

Ashishmathew01081987 · Answer

Here you have to find the relation between Side od Cube A and Side of Cube B

Let Sa = side of cube A
And Sb = Side of cube B

given, Va = 2* Vb

(Sa^3) = 2* (Sb^3)--------------- Till this step you are correct. See the below explanation to clear the doubt.

Taking Cube root on both sides

Sa = 2^(1/3) * Sb

Therefore answer is B

Divyadisha · Answer

Volume A= 2 Volume B

Side^3 (A) = 2 Side ^3 (B)
Side (A) = 2 ^1/3X Side (B)

B is the answer

bumpbot · Answer

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If the volume of cube A is twice that of cube B, the side of

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If the volume of cube A is twice that of cube B, the side of

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