Finding the radius of a sphere given the volume

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The video reviews how to find the radius of a sphere given the volume.
The question that is solved is,
Find the radius of a sphere with a volume of 72 meters squared.
The volume formula is 4/3 pi r cubed.
In order to solve for the radius you have to undo the formula.
Transcript
The radius of a sphere with a volume of 72 m^2
This is a backwards problem. There is no easy way to do it other than just to undo it. Let’s see what we have. We have the volume and we know that volume formula is equal to 4/3 pi radius cubed. We know the volume is 72 so I'm just going to plug in 72. Now the only variable we have in this formula is the radius, but we have to get it by itself by undoing all this stuff. To undo a fraction we multiply by its reciprocal so we are going to flip it upside down and multiply both sides by 3/4 and that cancels out the 4/3 so we will multiply 72 by 3/4 so let’s multiply 3 times 72 and divide that by 4 so the left side will simplify to 54 so we have 54 = pi radius cubed. We are getting closer. Now we need to get rid of pi which is 3.14 so we can just divide by that. We will take 54 and divide both sides by pi so 54 divided by pi and I get 17.9 is equal to radius cubed. Now how do you undo a cube? You take a cube root. What we will do is take the cube root of 17.9 I will show you what to do. Go to the Math button and under Math pick the 4th choice which is the cube root. You can choose it or go down to 4. Enter 17.9 and I will type in instead of pulling down my answer. I get 2.58, so our radius is 2.58 in meters. That is how you find the radius of a sphere from the volume. A little bit of undoing and algebra that you will manipulate.

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[bryannagarcia]

She literally saved my life. I have a test tommorow and this honestly helps me more than anyone knows. Thanks so much!!!!

[loganvandalen]

This is for a geometry class!!??? We are doing this in normal 8th grade math 0_o. Thanks for the help btw!

[uroobakhan]

i almost died in math yesterday lol thank you for this

[yeslastname]

This was by far one of the most comprehensible videos I've found, I did my problem alongside you with no prior knowledge and did it fairly easily, thank you so much!!

[imogenryan-kerr]

OH MY GOSH thank you so much for this video! Without it, I highly doubt I would be able to complete my assignment. THANK YOU! :)

[riverwing]

How do we plug this in with a scientific calculator?

[itzorca]

thank you sooo much, needed this for an assignment! congrats on 100k subs!

[cortycolemusic]

Thanks you so much! I couldn't have finished my assignment without your

[gkim]

Well, unfortunately we can't use calculator Idk how am I supposed to calculate these pi things 🥺

[herobrine]

Omg thank you sooo much this saved my life! see i have a test that will determine my grade tomorrow and this helps alot!!

[tiggotopia]

This was really helpful, but I can’t see what the 4th option is, plus I don’t have a calculator like that

[laurenmcshane]

Thank you, very helpful ! Very easy and to the point.

[DrEggs-dref]

Wait what if i don’t have or know the cube root since i don’t have that type of calculator

[jenaf]

Thank you so much! I saw this type of problem on my test but I had no idea how to do it- thank godness I still have tomorrow. But my calculator doesn't have that type of option to find the cube root... it there any other way?

[savannahsweeney]

I have a project due tomorrow and I have to make a test and answer the problems. Thank you for this!

[tamminar_]

3*V=x
x/4=y
y/pi=z
3cuberoot, z = final result

[rukamer]

Thank you so much, I have a test tomorrow and I was absent for this lesson. When my teacher tried to explain it to me I didn't understand. ~Rebecca

[trueclan]

Thanks helped with my summer homework !

[SeanGuiraud]

I haven't done this since 6th grade and I briefly forgot the formula. This was a nice refresher.

[luciak]

Pls tell me what if the 72 was a decimal? Such as 72.34. Would it be the same