Two different positions of the same dice are shown, the six faces of which are numbered from 1 to 6. What is the sum of the numbers that are opposite '5' and '1'?

8

Step 1) In figure 1  and 2

Step 2) Compare both the figure and we find out 1 and 5 both are common

Step 3)  Therefore 4 is the number which will be opposite to 3

Step 4 ) From all above points we conclude that the number which will be opposite to 1 and 5 is 2 and 6 and there their sum will be (6 + 2 = 8)