A cosmetics company that makes small cylindrical bars of soap wraps the bars in plastic prior to shipping. Find the surface area of a bar of soap if the diameter is 5cm and the height is 2cm.
Answers
we would have two circles of 5cm diameter each, and a rectangle of the length pi*diameter and 2cm, so lets add them: total = 2circles + rectangle total = 2(2*pi*(5/2)^2) + pi*diameter*heigth = 4*pi*(2.5)^2 + pi*5*2 = 109.9 that is the surface area of a bar soap 109.9 cm^2
The formula you use is pi x radius ^ 2 + pi x radius x l ( l stands for lateral height) pi x 2.5^2 + pi x 2.5(2) 3.14 x 6.25 + 3.14 x 5 19.6 + 15.7 = 35.3 cm^2