Answer:

Explanation:
step 1
Find the volume of the cylinder (hollow drum)
The volume is equal to
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we have
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
substitute
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step 2
Find the volume of one basketball
The volume of the sphere is equal to
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we have

substitute
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
step 3
Find the maximum number of basketballs that the cylindrical drum contains
so
Divide the volume of the cylinder by the volume of one basketball
