Thanks for pointing this out. That is a fairly jarring cut. I’ll speak to Ben and see if he can edit this video.
I think the cut may have originally been added to explain how multiplying a number by its reciprocal always equals 1.
Put simply, the reciprocal is just a number that’s been flipped on its head.
So in this case, 1/3 x 3/1 = 3/3 = 1.
Ben uses the pie example to try and represent this concept visually.
To get to the answer of 16 you can enter 4096^(1/3) on your calculator.
Since x^1 is just x, this means that x = 16.
You can also get there by taking the cube root of 4096, which will also give you the same result.
This is because one of the index laws, which states:
In our case, a = 4096, m = 3, and n = 1.
So we end up with a cube root and don’t have to do anything to the 4096, since it’s just being raised to the first power, which doesn’t change it.
I hope that helps clarify what’s going on but if you have any other questions please ask.