## anonymous 5 years ago right cylinder with a 90 degree slice remove?

1. anonymous

a cheese log

2. anonymous

3. anonymous

yea but i need to know how to do this problem

4. anonymous

You haven't given us a problem yet. I'll definitely help you if you can post what you want help with

5. anonymous

that is the question(up there)

6. anonymous

Do you need the volume, or the surface area, or what?

7. anonymous

volume

8. anonymous

Well that's simple Hikari. How many degrees are there in a circle? You know that it's 360 degrees. Well to find how much volume is in a right cylinder with 90 degrees removed, if you know the initial volume, you simply have to find the amount removed and subtract that from the intial value. To find how much you "cut away", you need to divide 90/360 to get the fraction of the cylinder you took away. Then you take this number and multiply it by the initial volume to get the amount you took away, and then subtract the amount you took away from the intial volume to get how much is left. Did that make sense to you?

9. anonymous

but i have the radius is 6 and the height is 12 but can u show me the equation of this problem

10. anonymous

Oh ok. You didn't give me the initial parameters!! Now we can move out of the theoreticals. How I would approach this problem is to envision a cylinder with r=6 and height=12. We know the volume of this (full) cylinder through the formula $V= 2\pi r^2 * h$ We plug everything in to get a volume of $v=864\pi$ Ok. So now we have the total volume of the cone (before we cut 0- degrees out)

11. anonymous

Now all we have to do is find out how much we cut out of the cylinder and subtract that from the total initial volume of the cylinder We know that 90/360 = 1/4 from my previous previous explanation. So to find the area we subtracted, we multiple 1/4*864pi to get 216pi. Now we subtract the value we took from the cylinder when we cut 90 degrees out. V= 864pi - 216pi = 648 pi

12. anonymous

oh i got thank but i am wonder if you can sent me your email so when i have my homework from geometry,you can help me

13. anonymous

I am posting another question right now

14. anonymous

15. anonymous

An oblique trapozidal prism. The trapozidal base has a height of 4 in. and base the measure 8 in. and 12 in. The height of the prism is 24 in.?

16. anonymous

Hey and if you need my email, it is TheAthenian1@gmail.com

17. anonymous

ok thank so much

18. anonymous

So what I'm thinking is how we find the volume for any prism (nice concept to keep in mind when solving these problems). Essentially, we take the area of the base and multiply it by the height to find the volume. To find the area of the base, we can divide the trapezoid into a rectangle and a triangle (one base will have 4 in. sticking out and will form one side of the triangle).

19. anonymous

can u show me equation please

20. anonymous

So in this case, we have a rectangle that is 8 x 4 (think base x height) and a triangle that is (4x4)/2 (area of a triangle) If we add these two values together, we get 40 in^2 for the area of the trapezoid. Then we multiply 40 in^2 by the height 12in to get 280in^3 for the volume

21. anonymous

In general, the volume of a prism = (area of base)(Height)

22. anonymous

so that answer for the volume?

23. anonymous

That's what I would think... Yes. But I have been known to be sloppy and make arithmetic mistakes in the past so it might be a good idea to check my answer as well!

24. anonymous

hey don't worry because my mom ask someone to help me but no one did not know how to do this but u help me

25. anonymous

Well I'm glad I could be of help! If you have any questions, feel free to email me or post here as there are some (I'm sure) very other good people who could help you as well. :)

26. anonymous

I will sent in email because that the only thing that I can use it