Answer:
D: 768
Step-by-step explanation:
First, he divides a piece of paper in half.

He gets two pieces.
Next, he cuts each of the pieces into three parts.

Thirdly, he cuts each of the 6 pieces into 8 pieces.

Lastly, he divides each piece into 16 parts.

He has 768 pieces in the end. (D)
If you imagine it like the picture below, you could use the pythagorean theorem to solve for x
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