The diameter of a circle is 16. By what number must the radius be decreased in order to decrease the area of the circle by $48\pi$?
<|im_start|>system
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<|im_start|>user
The diameter of a circle is 16. By what number must the radius be decreased in order to decrease the area of the circle by $48\pi$?
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<|im_start|>assistant

user
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The diameter of a circle is 16. By what number must the radius be decreased in order to decrease the area of the circle by $48\pi$?
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