19.042002

# a cylinder has a volume of 392.5 in and a height of 5 in a.find the radius of the cylinder b. find the surface area for the cylinder

crinny
Mathematics
1 10

a cylinder has a volume of 392.5 in and a height of 5 in a.find the radius of the cylinder b. find the surface area for the cylinder

volume=height times area of base area of base=circle=pi times r^2 subsitute volume=392.5 height=5 subsitute 392.5=5 times pi times r^2 divide both sides by 5 78.5=pi times r^2 aprox pi to 3.14 78.5=3.14 times r^2 divide both sides by 3.14 25=r^2 square root both sides 5=r A. Radius=5 in surface area=2(area of base)+(circunfernce times height) area of base=pi times r^2=3.14 times 5^2=78.5 circumference=2 times pi times r=2 times 3.14 times 5=31.4 height=5 surface area=2(78.5)+(31.4 times 5) surface area=157+157 surface area=314 A. radius=5 cm surface area= 314 cm^2