Question

Cylinder help..if the volume of a cylinder is 340 how do i find the perimeter, surface aria, and the hight

Answer 1

You know that the Surface Area equation of a cylinder right? which is:\[SA = 2\pi r^2 + 2\pi r H\]

and the volume is :
\[V = \pi r^2 H\]

Perimeter is :
\[P = 2\pi R\]

all you have to do is find a relationship between all of them and you'll be able to figure out the height, perimeter and SA , so you'll get :

Notice that the volume is = pi r ^2 h and the perimeter is = 2pi r so the SA can be written as :

\[SA = 2(340)H + PH\]

Answer 2

are you sure that that's the only given?

Answer 3

yep i am givin x 1-a2 i think that is the radious and i have to find all of those for numbers 1-12

Answer 4

x = 1- a2?

Answer 5

you need more given, I doubt that the only given is the volume lol

Answer 6

ok so the whole thing is a project we have to figure out what is best for making a box..we are given x values 1-12 and the volume of 340 cubic inches 1-12 i believe are the radices

Answer 7

i need to find the hight. the surface aria..and the perimeter of a cylinder

Answer 8

with that info

Answer 9

Alright, pick one of the radiuses and plug it in the Volume's equation to find H :) see if the number makes sense.

Answer 10

ok so i take piXr squared and get the hight?

Answer 11

for example .3.14X1 squared?

Answer 12

V = pi r^2 H , you can plug in any value or R, then find H, and after finding H you can plug it in the perimeter, and when you find the perimeter you'll be able to find the SA, the new equation that I have wrote up there ^_^

Answer 13

as far as I can go lol, since I don't have enough given

Answer 14

im not getting how you find h when you need it in the equation

Answer 15

alright, we have the volume right? :)

Answer 16

\[V = 340 \]

Answer 17

you have values of x, which are considered as the radius right?

Answer 18

so you can take R = 4 for example and plug it in the following equation:\[V = \pi r^2h\]

so we have R and V, we can solve for H, right?

Answer 19

lol, are you getting the idea now? :)

Answer 20

\[340=\pi(4) squared ?\]

Answer 21

actually it's :\[H = (340)/(8\pi)\]

and calculate it, that ofcourse if you choose your radius to be 4 ^_^ clear?

Answer 22

wait it's 32 pi instead of 8 pi I forgot to square it lol!

Answer 23

ok so i take x=340/r is this correct...if not i give up for the night and am going to bed..i am sure i am making this 100X harder than it actually is

Answer 24

and that will give me the hight ?

Answer 25

don't give up lol, alright, let's try once more!

WE have x values, right?

Answer 26

yes those values= the radius...so if the virst x value is 1 how do i get the hight?

Answer 27

it's simple, just take your time and concentrate with me

Answer 28

Okay so x = r = 1

we have given:

R = 1
V = 340

find H= ?

Answer 29

yep thats what i need to do...now how?

Answer 30

The equation is :

\[V = \pi r^2 h\]

Answer 31

plug in the given in the equation and solve for H :

340 = pi (1)^2 H
H = 340/pi
H = 108.23 in ^_^

Answer 32

we have found the height now :)

Answer 33

now we need to find the perimeter right?

Answer 34

are you following me lol? =P wakey wakey~

Answer 35

hold on

Answer 36

okay ^_^

Answer 37

ok so the hight for a radios of 1 is 108.2 correct

Answer 38

excellent!

Answer 39

ok so now perimeter

Answer 40

now, we can find the perimeter right? The equation is :

P = 2pi R

we have R = 1, solve :)

Answer 41

ok so i take \[2piX(1)squared\]

Answer 42

i got 6.28

Answer 43

lol no, the equation is :\[P = 2 \pi R\]
substitute R in the equation and you'll get P ^_^

Answer 44

lol yeah , that's right :)

Answer 45

now, we can find the SA right?

Answer 46

ok so now the SA

Answer 47

The equation is :\[SA = 2\pi r^2 + 2\pi r h\]
we have R = 1 and H = 108.2

substitute the given and solve ^_^

Answer 48

i got 686.1

Answer 49

very good !

Answer 50

you have solved the question using R = 1 ^_^

did you get the idea now? :)

Answer 51

ok let me make sure i can get this for 2 now and then ill let you go..if you dont mind

Answer 52

good morning

Answer 53

hi

Answer 54

alright, it's the same idea blackford, but different values for R ^_^, good morning andy

Answer 55

same way of solving , good luck! ^_^

Answer 56

i got 120.8

Answer 57

for?

Answer 58

the hight with a radios of 2

Answer 59

hmm it should be 27.06

(340)/(4pi) = H

H = 27.06 in

Answer 60

and andy going quite lol

Answer 61

oops i see i think..i just realized you want h by itself

Answer 62

yep ^_^ since we want to find it

Answer 63

ok for a R of 3 i got 12.02 for the hight..correct?

Answer 64

excellent ^_^

Answer 65

ok i think i am getting it now

Answer 66

you got the idea now :)

Answer 67

you can proceed on your own right?

Answer 68

for now thank you :)

Answer 69

np ^_^

Answer 70

i got a new one

Answer 71

alright

Answer 72

now for a square pyramid. this time i need the hight,perimeter, SA, and lateral aria

Answer 73

volume still 340 and same x values 1-12

Answer 74

All you have to do is write down the new equations for the square pyramid

Answer 75

i think that x= base length now

Answer 76

Volume is :
\[V = (b^2h)/3\]

Surface Area is :
\[SA = 2bs + b^2\]

and perimeter :

\[P = (\S-B)(1/2)(l)\]

find the relationship and solve ^_^ same idea as the previous one :)

Answer 77

P = (S-B)(1/2)(L) *

Answer 78

oh and the lateral area is = PL/2 where P = perimeter and L = slant height ^_^

Answer 79

ok so 340=1squared(h)/3

Answer 80

oh yeah i want the slant hight not lateral aria

Answer 81

so \[340=1^2(h).....340=1/3 =.33 340/.33..correct or no\]

Answer 82

340(3) = h
h = 1020

Answer 83

lol, I see what's your problem, you got the idea, but have trouble with calculation, take your time answering the questions :) step at a time ^_^