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Question

what is the volume of the two hemispheres and one cylinder combined rounded to the nearest tenth of an inch? Use 3.14 for pi radius=6inches height=18inches

Answer 1

about 1.7 cubic feet

= about 2937.6 cubic inches

radius = r = 6 inches = .5 ft

height = h = 18 inches = 1.5 ft

volume = 4/3)pi(r^3) + hpi(r^2)

= (4/3)pi(.5^3) + 1.5pi(.5^2)

= pi((4/3)(.125) + 1.5(.25)

=pi((4/3(1/8)+(3/2)(1/4))

= pi(1/6+3/8)

= pi(4/24+9/24)

=13pi/24

= about 13(3.14)/24

= about 1.7 ft^3

= about 1.7(12^3)= 1.7(1738) = 2937.6 cubic inches