whats the cost ofthe material to make the cylinder?

Question

it is necessary to make a copper cylinder 160cm long and 112cm in diameter. the cylinder is to be cosed at both ends.

find the cost of the material required to make the cylinder if the copper costs $15.50 per square meter

Answer 1

I'm assuming the cylinder is hollow.

First convert everything to meters to keep your units consistent:
L=160 cm=0.16 m
D=112 cm=0.112 m

Now, calculate the total surface area of the cylinder: You have two circles (one on top, one on bottom) and the side (which is really just a big rectangle wrapped around).
A=2*PI*R^2+PI*D*L.
A=0.07600 m^2.

If the cost is $15.50 per square meter and you require 0.076 square meters of copper, then your total cost will be:
C=0.076*15.50=$1.178. Round to the nearest cent: $1.18

Answer 2

determine the square meters of coper. you need the area of the surface of the cylinder.
area of a circle a=pi *r^2
you can take the circumfrance of the circle times the height to find the area of the sides C=pi*d
Add 2 ends and the side and you have the area. then multiply by 15.50 to get the cost.
divide by 100 to convert to meters.
$11780.22

Answer 3

A = πr(2r + h)
C =A*c = cπr(2r + h)
C = ($15.50/m^2)(1 m^2/ 10^4 cm^2)π112(2*112 + 160)
C = $209.43 + waste