Answer:
9π in², about 28.27 in²
Explanation:
The area of a circle is given by the formula ...
A = π·r² . . . . . where r is the radius
Here, the diameter is 12 in, so the radius is 6 in. The area of the entire pizza is then ...
A = π·(6 in)² = 36π in²
Jason ate 1/4 of it, so ate an area that is ...
(1/4)·36π in² = 9π in² ≈ 28.27 in²
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Comment on the problem
The problem statement tells you Jason ate 1/4 of a 12-inch pizza. The problem statement does not ask for that quantity to be expressed in any other unit of measure.