Sara made a wax model of a rolling pin of diameter 10 cm. The rolling pin was shaped like a right circular cylinder with a right circular cone at each end as shown below. Sara made a wax model of a rolling pin of diameter 10 cm. The rolling pin was shaped like a right circular cylinder with a right circular cone at each end as shown below.

Question

anonymous · Answer

attachment

anonymous · Answer

tips?

phi · Answer

what is the question?

anonymous · Answer

Sara made a wax model of a rolling pin of diameter 10 cm. The rolling pin was shaped like a right circular cylinder with a right circular cone at each end as shown below. Sara made a wax model of a rolling pin of diameter 10 cm. The rolling pin was shaped like a right circular cylinder with a right circular cone at each end as shown below.

anonymous · Answer

What was the total surface area of the rolling pin? Using complete sentences, describe the steps you used to calculate the surface area.

phi · Answer

See http://en.wikipedia.org/wiki/Cone_(geometry)#Surface_Area for the area of a cone.

anonymous · Answer

ehhhh

anonymous · Answer

the surface area of a cone is pie(radius)(slant height) plus pie(radius squared)

anonymous · Answer

right?

phi · Answer

this part
plus pie(radius squared)
is the bottom of the cone which is glued to the cylinder, so we don't see it.  (If we were painting the rolling pin, it would not be painted)

anonymous · Answer

k.....

anonymous · Answer

wouldn't the area of the rectangular part be 140?

anonymous · Answer

10 would be its width, right?

phi · Answer

are you asking about the cylinder?  cylinders are round.
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