ISRO2014-65

Question

A cube of side $1$ unit is placed in such a way that the origin coincides with one of its top vertices and the three axes along three of its edges. What are the co-ordinates of the vertex which is diagonally opposite to the vertex whose co-ordinates are $(1, 0, 1)?$

• A. $(0, 0, 0)$
• B. $(0, -1, 0)$
• C. $(0, 1, 0)$
• D. $(1, 1, 1)$

Comments

It can be c also right??

Answer 1

It should be B

Draw the cube according to given information

Comments

It can be C also.. Isn't?

Answer 2

The question says “three axes along three of its edges”. 

If we draw a diagram accordingly, A corresponds to the point (1,0,1) whose diagonally opposite point will be B (0,1,0).

You can choose any vertex as the origin and draw the axes, the answer would remain the same.