Faces - DS

[karthikpandian19]

What fractional part of the total surface area of cube C is red?
(1) Each of 3 faces of C is exactly 1/2 red.
(2) Each of 3 faces of C is entirely white.

[rijul007]

What fractional part of the total surface area of cube C is red?
(1) Each of 3 faces of C is exactly 1/2 red.
(2) Each of 3 faces of C is entirely white.

(1) Each of 3 faces of C is exactly 1/2 red.


We dont know what fraction of other 3 faces are red

Insufficient


(2) Each of 3 faces of C is entirely white.

Again we dont know what fraction of other faces is red


Combing the two statements
Each of 3 faces of C is exactly 1/2 red.
Each of 3 faces of C is entirely white.

We know that out of 6 faces, area of exactly 3 facs is exactly 1/2 red
Fraction part = (3/2)/6 = 1/4


Option C

[Anurag@Gurome]

What fractional part of the total surface area of cube C is red?
(1) Each of 3 faces of C is exactly 1/2 red.
(2) Each of 3 faces of C is entirely white.

(1) Each of 3 faces of C is exactly 1/2 red but nothing has been said about the other 3 faces, some fraction of the other 3 faces may be red, about which we are not sure; NOT sufficient.

(2) Each of 3 faces of C is entirely white but again nothing has been said about the other 3 faces; NOT sufficient.

Combining (1) and (2), we clearly know that 1/2 of 3 faces is red while the other 3 faces are entirely white, so fractional part of the total surface area of cube C, which is red = 1.5/6 = 1/4; SUFFICIENT.

The correct answer is C.

[ArunangsuSahu]

No need to SOLVE

1) No info about the remaining 3 faces. They can be full red or white. INSUFFICIENT
2) No info about the remaining three faces. They can be half Red or Full Red. INSUFFICIENT

COMBINING, It gives 6 areas.. SO SUFFICIENT

(C) is t he answer