What is the length of an edge of a cube whose total surface area is X cm2 and whose total surface area is (frac{X}{2})cm3?
-
A.
3 -
B.
6 -
C.
9 -
D.
12
Correct Answer: Option A
Explanation
Total surface area of cube = 6s2
6s2 = x
s2 = x = (frac{x}{6})…..(1)
volume of a cube = s2 = (frac{x}{2})
s2 = (frac{x}{2})……(2)
put(1) into (2)
s((frac{x}{6})) = (frac{x}{2})
s = (frac{x}{2} times frac{6}{x})
= 3cm