Answer:
52,227.4 square feet
Explanation:
The area of the field not covered by the silo is the difference between the area of the rectangular field and the area of the circular base of the silo.
The field area is given by the formula ...
A = LW . . . . where L and W represent length and width
The area of the circular base of the silo is given by the formula ...
A = πr² . . . . where r represents the radius of the silo (half the diameter)
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The desired difference is ...
A = LW - πr² = (160 ft)(330 ft) -π(13.5 ft)² ≈ 52800 ft² -572.6 ft²
A ≈ 52,227.4 ft²
About 52,227.4 square feet are left for planting.
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Additional comment
Sometimes, you are expected to round the answer to a precision matching the precision of the contributors. Here, that would be 2 significant figures:
52,000 ft²
You may be expected to give your answer rounded to a precision other than either of the values shown above.