You roll a six sided die three times. what is the size of the sample space after those three rolls?

216 is the answer to it

The answer is 216 because we will compute 6^3 = 6*6*6 = 36*6 = 216

If we had 2 dice rolled out, then it would be 6^2 = 6*6 = 36. For each die added, we multiply another 6 because the die has 6 sides.

Visually, 2 dice form a 2D table of 36 possible outcomes. Three dice form a 3D cube of possible outcomes (a 6 by 6 by 6 cube with volume 216). You can think of it like a rubix cube. Each sub-block would house a possible combo such as {2,1,7} meaning that you rolled a '2' on the first die, a '1' on the second die, and a '7' on the third die.

Note: rolling a single die 3 times will produce the same sample space as rolling three separate dice 1 time.