Two different positions of the same dice are shown, the six faces of which are numbered from 1 to 6. Select the number that will be on the face opposite to the one showing 6.

3

Step 1) In figure 1  and 2

Step 2) Compare both the figure and we find out 2 and 5 both are common

Step 3)  Therefore 3 is the number which will be opposite to 6