Question

Sean used candle molds, as shown below, to make candles that were perfect cylinders and spheres:

Picture Will Be Attached!

What is the approximate difference in the amount of wax needed to make a candle from each of these molds? Use π = 3.14.

18.0 cubic inches
28.26 cubic inches
37.0 cubic inches
56.52 cubic inches

Answer 1

Am I right with D?

Answer 2

@pooja195

Answer 3

Hello,
so we need to find the volume of both:
Volume of cylinder= pi * r^2 * h
Volume of Sphere= (4/3) * pi * r^3

Answer 4

Okay.

Answer 5

We can start with cylinder what is the height and radius?

Answer 6

6in and 3in

Answer 7

pi*3^2*6=?

Answer 8

169.56

Answer 9

Good, next we do the same for the sphere
what is the radius?

Answer 10

is it 3in?

Answer 11

Yep
Volume of Sphere= (4/3) * pi * 3^3=?

Answer 12

37.69911184311

Answer 13

18

Answer 14

Now you multiply 18 x 3.14 right?

Answer 15

\(\color{#0cbb34}{\text{Originally Posted by}}\) @Gucchi
37.69911184311
\(\color{#0cbb34}{\text{End of Quote}}\)
How did you get this?

Answer 16

I did what you told me to do

Answer 17

\(\color{#0cbb34}{\text{Originally Posted by}}\) @pooja195
Yep
Volume of Sphere= (4/3) * pi * 3^3=?
\(\color{#0cbb34}{\text{End of Quote}}\)

Answer 18

yall need help?

Answer 19

When you do it in a calculator you will get: 113.097336

Answer 20

I must've done it wrong

Answer 21

Sorry.

Answer 22

so do yall need help or nah

Answer 23

I think I multiplied by 3 incorrectly

Answer 24

It may have been the way it was typed no worries.
So next we will go ahead and find the difference of the two. Disregard the 18.
169.56-113.10=?

Answer 25

They gave a value for pi so we will include it in the formula. Apologies.

Answer 26

56.46

Answer 27

@grantjr you are more than welcome to pitch in your thoughts :-)

Answer 28

There was a slight rounding error in the first one for the volume of cylinder but the answer you had of D is correct.

Answer 29

Oh ok.

Answer 30

Essentially you would use both formula's of finding the volume and then you would find the difference of the two given volumes.

Answer 31

That's true. Thank you.

Answer 32

:-)