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If the perimeter of one face of a cube is 48 cm, then its volume is:
729 cm3
1728 cm3
512 cm3
1024 cm3
1728 cm3
Since the perimeter of a square face is 4a, divide 48 by 4 to get side a=12 cm, then cube it (123=1728).
Perimeter of one face of a cube = 48 cm
V=a3
Since the perimeter of a square face is 4a, divide 48 by 4 to get side a=12 cm, then cube it (123=1728).
Confusing the perimeter of one face (4a) with the total length of all edges of a cube (12a).
Understand the given information
A cube has 6 identical square faces. The perimeter of one face is given as 48 cm.
Perimeter=4a=48
Find the side length of the cube
Since each face is a square with side a, its perimeter is 4a. Dividing 48 by 4 gives the side length a.
a=448=12 cm
Calculate the volume of the cube
The formula for the volume of a cube is V=a3. Substituting a=12 cm into the formula:
V=123=1728 cm3
B is correct because the side length of the cube is 12 cm and its volume is 123=1728 cm3.
Always verify whether the question refers to the perimeter of a single face (4a), total edge length (12a), or total surface area (6a2) before calculating volume.