Question

find the surface area of the cylinder to the nearest tenth of a square unit

width: 4cm
height: 12.4cm

a: 206cm(2)
b: 623cm (2)
c: 100.5cm (2)
d: 412cm (2)


i think it’s b, can someone give me the right answer quick pls. <3

Answer 1

why do you think it's b? Did you show some work?
You have the two circular bases, plus the curved lateral area
By width, do you mean diameter? If so, then the radius is 2.
A = 2πr^2 + 2πrh = 2πr(r+h) = 2π*2(2+12.4) = 57.6π = 176

Maybe you have a typo, as that is not one of the choices

Answer 2

no that person didnt have a typo

Answer 3

I did that but I can’t remember if I got it right or not🥲… DON’T take my word for it, but heres what I did. I did 3.14 x 4 (the radius not width) ^2. I did 4x4 and got 16. Then I did 3.14 x 16 and got 50.24. The formula is pi(the symbol) r^ 2 h so I multiplied 50.24 by the height 12.4. I got 622.976 and rounded up to 623. Thats what I got but IM NOT SURE if it’s right so pls only take me answer if you don’t mind getting one question wrong!

Answer 4

formula of a cylinders surface area:
2Πrh + 2Πr ^2
OK LETS START

1st part of equation ( 2Πrh )
2 x Π x r x h
2 x 3.14 x 4 x 12.4 =
311.488

2nd part of equation ( 2Πr ^2 )
2 x Π x (r^2)
2 x 3.14 x (4^2)
2 x 3.14 x (16)
6.28 x 16 =
100.48

Now add them:
311.488 +100.48 =
411.968
Round up to 412 <33

Answer 5

1. C
2. A
3. C
4. D
5. A
6. B
7. C
8. C
For Connexus. 100%