Question

1. The surface area of a cylinder is T=2rtrh+2tr2, where T is the surface area, andr

is the radius of the base. A penny is a cylinder with a diameter of 19.05 millimeters
and a thickness of 1.55 millimeters. Ignoring the raised design, what is the surface
area of a penny?
Pls help

Answer 1

the surface area of a penny = 662.81 mm²

Explanation:

got this correct in exam

Answer 2

the surface area of a penny = 662.81 mm²

Explanation:

given:

A penny is a cylinder with a diameter of 19.05 millimeters

and a thickness of 1.55 millimeters.

find:

what is the surface area of a penny?

surface area of a cylinder formula:

As = 2 π r h + 2 π r²

let r = 19.05 / 2

r = 9.53 mm

let h = 1.55mm

plugin values into the formula:

As = 2 π (9.53) 1.55 + 2 π (9.53)²

As = 92.76 + 570.05

As = 662.81 mm²

therefore,

the surface area of a penny = 662.81 mm²