Question

I need help. The volume of a right cylindrical water tank is 26,374.14 cubic cm. The area of the base of the cylinder is 720.63 square cm. What is the height (length) of the water tank?
a)

109.796 cm

b)

36.60 cm

c)

27.449 cm

d)

11.65 cm

Answer 1

Volume of cylinder = area of base x height of cylinder

Answer 2

I'm looking for the height.

Answer 3

it has to be one of those options.

Answer 4

So rearrange the formula I have given you to find the height, since you know what the volume and area of the cylinder is. :)

Answer 5

my answer does not match any of the options.

Answer 6

What is your answer, and how did you get the answer?

Answer 7

The radius is what of the base?

Answer 8

my answer was 0.016

Answer 9

How did you get your answer?

Answer 10

26374.14/pi*720.63^2=0.016166

Answer 11

720.63 is the AREA of the base of the cylinder. 720.63 is not the radius of the base of the cylinder

Answer 12

Oh wait sorry I misread the problem.

Answer 13

Yes @Bobo-i-bo that is correct the radius is half.

Answer 14

oh

Answer 15

You need to use my formula:
volume of cylinder = area of base x height of cylinder

Answer 16

but what's the half of 720.63?

Answer 17

Here is the formula for height.

Answer 18

Half of 720.63 is 360.315

Answer 19

You can find this by multiplying 720.63 by 0.5.

Answer 20

I have no idea what you're doing @jchick ...

Answer 21

Finding the radius @Bobo-i-bo

Answer 22

All I did was find half of 720.63 @Bobo-i-bo

Answer 23

so which means the answer is...

Answer 24

why do you need to find the radius?

Answer 25

I'm trying to find the height

Answer 26

We are trying to find the height of a right cylinder if I am not mistaken the formula asks for the radius.

Answer 27

so the answer to the question is...

Answer 28

Do you want the answer or the method?

Answer 29

the answer

Answer 30

I can't give that.

Answer 31

No direct answers, please. Instead, show the work you have already done, so that we could give you appropriate feedback.

Answer 32

i think 36.60 maybe?

Answer 33

Volume of a vertical cylindrical tank: V=b*h, where b is the area of the base and h is the height. Please, show your calculations, as seeing them is the only way in which I can figure out your efforts.

Answer 34

Let's say the volume is 26,374 cubic cm, and that the area of the base is 721 square cm.
Using the formula I gave you, figure out the height. Hint: solve V=b*h for h.

Answer 35

@pucusana @mathmale is the best I know at math so you are in great hands with him!

Answer 36

Thank you very much, @jchick!

Answer 37

Not a problem @mathmale because even when the problem confuses me you are right on track!

Answer 38

Example: Supposing we had a right rectangular block of base area 100 square inches and volume 250 cubic inches. Since V = base * height, the height is (volume) / (base).

Dividing the volume (250 cubic inches) by the base (100 square inches), we get

250 cu in
-------- = 2.5 in (as the height of the block).

Now, supposing that this right circular cyl. has a base area of
100 sq in

Answer 39

721 square cm and that the volume is 26374 cubic cm.
What is the height of the cylinder? Use precisely the same method as I did in the example, above.

Answer 40

@mathmale I have done some work I would appreciate if you could tell me if I am correct or not.

Answer 41

Like I said this problem was confusing me.

Answer 42

Just divide the volume by the given area of the base. Even after rounding off the given info, the result (37 cm) is enough to enable us to find the correct answer (36.60 cm). Hope this problem now seems more solveable.

Answer 43

I came up with something different.

Answer 44

@jchick : The work you shared looks like this:\[\frac{ A }{ 2 \pi r }=\frac{ 26374 }{ 2 \pi (360.31) }\]

Answer 45

Recognizing that the height is the volume divided by the area of the base, my result is:\[\frac{ V }{ A }=\frac{ 26374 cm^3 }{ 721 cm^2 }=36.6 cm=height\]

Answer 46

Note that your formula, 2pi(r), is for the circumference of the base, not for the area. Since the area is already known / given, and is 721 sq cm, just divide the volume by the area of the base to obtain the height of the cyl.

Answer 47

Ah ok I see my error.