Alec's Surface Area Post

First find the radius
r=d/2
r=7/2
r=3.5

Since I have the diameter already I'm going to find the circumference
c=πd
c=3.14x7
c=21.98

Then find the area of the circle
a=πrr
a=3.14x3.5x3.5
a=38.47 square cm ( I round up to the nearest hundredths)

I now have the area of the 2 circle so I need to find next is the area of the square
a= lxw (l is the circumference)
a=21.98x7
a=153.86 square cm.

Add the area of the 2 circle and the rectangle
38.47+38.47+153.86= 230.8square cm
TSA= 230.8square cm


I'm gonna use another way to solve this question
(2πrr) + (2rπh)
(2x3.14x3x3) + (2x3x3.14x5)
=56.52 =94.2
Then add those 2 answer to get the TSA
56.52+94.2=150.72square cm.


(2πrr) + (2rπh)
(2x3.14x6.5x6.5)+(2x6.5x3.14x20)
=265.33 =816.4
265.33+816.4=1081.73square cm
TSA=1081.73square cm

r=d/2
r=20/2
r=10cm
(2πrr)+(2rπh)
(2x3.14x10x10)+(2x10x3.14x40)
628+2512
3140cm^2

r=d/2
r=30/2
r=15
(2πrr)+(2rπh)
(2x3.14x15x15)+(2x15x3.14.20)
1413+37680=39093
The fat one is the better deal because it has more capacity.