A machinist creates a spacer by drilling a 3 cm diameter hole through the middle of a cylinder that has a diameter of 5 cm and a height of 0.5 cm. What is the volume of the finished spacer to the nearest tenth cm3?
We subtract the two volumes
π25*0.5 - π9*0.5 = 0.5π(25-9) = 0.5π * 16 = 8π.
That's 25.13 so 25.1
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