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The total surface area of a cube is 54.
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25 Nov 2020, 09:24
25 Nov 2020, 09:24
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The total surface area of a cube is 54.
A)The quantity in Column A is greater.
B)The quantity in Column B is greater.
C)The two quantities are equal.
D)The relationship cannot be determined from the information given.
Kudos for the right answer and explanation
Quantity A |
Quantity B |
The length of a diagonal of one face of the cube |
3 |
A)The quantity in Column A is greater.
B)The quantity in Column B is greater.
C)The two quantities are equal.
D)The relationship cannot be determined from the information given.
Kudos for the right answer and explanation
Re: The total surface area of a cube is 54.
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31 Dec 2020, 19:58
31 Dec 2020, 19:58
1
Surface area of cube is given 54
Formula for Surface area of a cube = 6 * a^2 (a= side of the cube)
6 * a^2 = 54
a^2=9
a=3
Qt A
The length of a diagonal of one face of the cube
It is calculated as = side * \sqrt{2}\
= 3\sqrt{2}\
Qt B
3
Qt A > Qt B
Answer A
Formula for Surface area of a cube = 6 * a^2 (a= side of the cube)
6 * a^2 = 54
a^2=9
a=3
Qt A
The length of a diagonal of one face of the cube
It is calculated as = side * \sqrt{2}\
= 3\sqrt{2}\
Qt B
3
Qt A > Qt B
Answer A
Re: The total surface area of a cube is 54.
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03 Feb 2021, 21:01
03 Feb 2021, 21:01
1
There are some formulas you have to remember for the GRE test. In the geometry section you should have a solid grasp of the course material on Circles, Triangles, Squares and Cubes in a standalone as well as a combination of the shapes.
Coming to the question,
The surface area of a cube is given by the formula \(6l^2\); where l = length of a side of the cube.
We are given with the diagonal of one side of the cube. We know that the diagonal and two sides of the cube form a 45-45-90 triangle.
In such a 45-45-90 triangle sides are in the proportion of \(x:x:x\sqrt{2}\)
From the question:
Now, \(6l^2\) = 54
or, \(l^2\) = 9
or, \(l\) = 3
Hence the two sides of the cube are 3 each and the diagonal is 3\(\sqrt{2}\).
Therefore, A is the answer.
Coming to the question,
The surface area of a cube is given by the formula \(6l^2\); where l = length of a side of the cube.
We are given with the diagonal of one side of the cube. We know that the diagonal and two sides of the cube form a 45-45-90 triangle.
In such a 45-45-90 triangle sides are in the proportion of \(x:x:x\sqrt{2}\)
From the question:
Now, \(6l^2\) = 54
or, \(l^2\) = 9
or, \(l\) = 3
Hence the two sides of the cube are 3 each and the diagonal is 3\(\sqrt{2}\).
Therefore, A is the answer.
