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#26 Re: Help Me ! » Surface Area and Volume of Spheres, Cylinders, and Cones » 2013-11-04 06:02:44
1. If a hexagon has a side of 3 units, what is the area of the hexagon?
2. If a hexagon has an area of 100 units, what is the length of one side?
3. If a hexagon has a radius (center to point of angle) of 6, what is the side of the hexagon?
4. If a hexagon has a radius (center to point of angle) of 6, what is the area of the hexagon?
5. If a hexagon is resting on a flat side, and has a total height of 18, what is the length of each side of the hexagon?
6. If a hexagon is resting on a flat side, and has a total height of 18, what is the area of the hexagon?
7. Problem solver (worth 4 points): Come up with a way to find the area and volume of a football. Include in your answer a way to acquire any necessary measurements without cutting or otherwise destroying the football. Also include all necessary formulas to implement your idea. (You don't need to find actual numbers, just outline the method in step by step detail--think of all the measurements you'll need to acquire and how you'll get them.)
#27 Re: Help Me ! » Surface Area and Volume of Spheres, Cylinders, and Cones » 2013-11-04 06:00:33
I sent them in and got 20/20 B) Thanks! I need help with some questions from the next lesson.
#28 Re: Help Me ! » Surface Area and Volume of Spheres, Cylinders, and Cones » 2013-11-04 05:55:30
18. What would the slant height of the cone be?
sqrt of (r^2 + h^2)
sqrt of (81 + 144)
sqrt of 225
= 15 (A)
19. Surface area of cone
T = (PI)rs + (PI)r^2
t = pi * 9 * 15 + pi * 9^2
t = pi * 135 + pi * 81
t = 135pi + 81pi
t = 216pi (B)
20. Volume of the cone
V = (1/3)(PI)(r^2)h
v = (1/3) * pi * 9^2 * 12
v = (1/3) * pi * 81 * 12
v = (1/3) * 972pi
v = 324pi (F)
Good?
#29 Re: Help Me ! » Surface Area and Volume of Spheres, Cylinders, and Cones » 2013-11-04 05:49:31
11. sqrt of (16^2 + 12^2)
= sqrt of (256 + 144)
= sqrt of 400
= 20 (E) Alright!!
12. Surface area of cone
T = (PI)rs + (PI)r^2
t = pi * 12 * 20 + pi * 144
t = 240pi + 144pi
t = 384pi (D)
13. Volume of the cone
V = (1/3)(PI)(r^2)h
v = (1/3) * pi * 144 * 16
v = (1/3) * pi * 2304
v = 1/3 * 2304pi
v = 768pi (E)
Are those correct?
#30 Re: Help Me ! » Surface Area and Volume of Spheres, Cylinders, and Cones » 2013-11-04 05:33:45
I didn't know how to do it. I'll put 5
How do I do #12 and #13
#31 Re: Help Me ! » Surface Area and Volume of Spheres, Cylinders, and Cones » 2013-11-04 05:09:10
4) D
5) A
6) C
7) B
8) A
9) D
10) D
I need help with 11, 12, and 13
#32 Re: Help Me ! » Surface Area and Volume of Spheres, Cylinders, and Cones » 2013-11-04 05:05:38
I got (F) for #3
#33 Re: Help Me ! » Prisms and Pyramids » 2013-11-04 04:57:07
What is the answer to number 5?
D or A? Or something else?
#34 Re: Help Me ! » Surface Area and Volume of Spheres, Cylinders, and Cones » 2013-11-04 04:54:43
No problem. Take all the time you need! 
#35 Re: Help Me ! » Surface Area and Volume of Spheres, Cylinders, and Cones » 2013-11-04 04:08:17
7. surface area of the sphere
4 * pi * r^2
a = 4 * pi * 12^2
a = 144pi * 4
a = 576pi (B)
8. volume of the sphere
V = (4/3)(PI)r^3
v= 4/3 * pi * 12^3
v= 4/3 * pi * 1728
v = 2304pi (A)
9. surface area of the cylinder
T = 2(PI)rh + 2(PI)r^2
t = 2 * pi * 192 + 2pi * 144
t = 384pi + 144 * 2pi
What do I do now?
10. volume of the cylinder
V = (PI)(r^2)h
v = pi * 12^2 * 16
v = pi* 144 * 16
v = 2304pi (D)
Sorry for all these posts!
I got 3 and 9
3 is (F) and 9 is (D).
14. surface area of the sphere
4 * pi * r^2
4 * pi * 9^2
4 * pi * 81
= 324pi (A)
15. volume of the sphere
V = (4/3)(PI)r^3
v = 4/3 * pi * 9^3
v = 4/3 * pi * 729
v = 972pi
16. surface area of the cylinder
T = 2(PI)rh + 2(PI)r^2
t = 2 * pi * 108 + 2 * pi * 81
t = 216pi + 162pi
t = 378pi (D)
17. volume of the cylinder
V = (PI)(r^2)h
v = pi * 9^2 * 12
v =pi * 81 * 12
v = 972pi (E)
Okay so I need help with 11, 12, 13, 18, 19, 20.
Are those all correct now till now?
#36 Re: Help Me ! » Surface Area and Volume of Spheres, Cylinders, and Cones » 2013-11-04 03:34:19
5. Surface area of cone
T = (PI)rs + (PI)r^2
t = pi * 6 * 10 + pi * 6^2
t = 60pi + 36pi
t = 96pi (A)
6. Volume of the cone
V = (1/3)(PI)(r^2)h
v = (1/3) * pi * 6^2 * 8
v = 1/3 * pi * 36 * 8
v = 96pi (C)
I also think I figured out the next step for number 3
T = 2(PI)rh + 2(PI)r^2
t = 2 * pi * 48 + 2(pi) * 6^2
t = 2 * pi * 48 + 2pi * 36
t = 96pi + 36 *2pi
Then what?
#37 Re: Help Me ! » Surface Area and Volume of Spheres, Cylinders, and Cones » 2013-11-04 03:27:51
2. V = (4/3)(PI)r^3
v= (4/3) * pi * 216
v = 288pi (B)
3. T = 2(PI)rh + 2(PI)r^2
t = 2 * pi * 48 + 2(pi) * 6^2
t = 2 * pi * 48 + 2pi * 36
What next?
4. V = (PI)(r^2)h
v = pi * 6^2 * 8
v = pi * 36 * 8
v = pi * 288
v = 288pi (D)
#38 Re: Help Me ! » Surface Area and Volume of Spheres, Cylinders, and Cones » 2013-11-04 03:20:02
Oh wait I got it. Volume of sphere = (4/3)(PI)r^3
and
surface area of cylinder is T = 2(PI)rh + 2(PI)r^2
cylinder volume is V = (PI)(r^2)h
I'll do numbers 2, 3, 4 and post them now.
#39 Re: Help Me ! » Surface Area and Volume of Spheres, Cylinders, and Cones » 2013-11-04 03:13:04
1. area = 4 * pi * r^2
area = 4 * pi * 6^2
area = 4 * pi * 36
area = 144pi
What are the two formulas for number 2 and 3?
#40 Re: Help Me ! » Areas Review » 2013-11-03 20:33:55
I have posted the new lesson I needed help with.
I named it "Surface Area and Volume of Spheres, Cylinders, and Cones"
Thanks again!
#41 Help Me ! » Surface Area and Volume of Spheres, Cylinders, and Cones » 2013-11-03 20:31:55
- rogerwaters
- Replies: 65
Hi,
Could you help me with this lesson. Any help is appreciated.
Thank you!
What is surface area and volume of the given shape, if the radius is 6, the height is 8, and the slant height is 10. (Not all shapes will require all three numbers.)
1. surface area of the sphere
A 144*pi
B 324*pi
C 456*pi
D 160*pi
E 173*pi
F 297*pi
2. volume of the sphere
A 214*pi
B 288*pi
C 165*pi
D 489*pi
E 346*pi
F 228*pi
3. surface area of the cylinder
A 654*pi
B 184*pi
C 124*pi
D 656*pi
E 247*pi
F 168*pi
4. volume of the cylinder
A 537*pi
B 987*pi
C 478*pi
D 288*pi
E 576*pi
F 454*pi
5. surface area of the cone
A 96*pi
B 78*pi
C 45*pi
D 24*pi
E 33pi
F 36*pi
6. volume of the cone
A 65*pi
B 46*pi
C 96*pi
D 32*pi
E 44*pi
F 28*pi
What is surface area and volume of the given shape, if the radius is 12, the height is 16. (Not all shapes will require both numbers.)
7. surface area of the sphere
A 196*pi
B 576*pi
C 248*pi
D 493*pi
E 165*pi
F 346*pi
8. volume of the sphere
A 2304*pi
B 2491*pi
C 3780*pi
D 1258*pi
E 2560*pi
F 5145*pi
9. surface area of the cylinder
A 345*pi
B 159*pi
C 781*pi
D 672*pi
E 248*pi
F 489*pi
10. volume of the cylinder
A 2485*pi
B 1964*pi
C 2501*pi
D 2304*pi
E 5499*pi
F 1059*pi
11. What would the slant height of the cone be?
A 54
B 16
C 35
D 12
E 20
F 91
12. surface area of the cone (with the slant height from # 11)
A 159*pi
B 215*pi
C 621*pi
D 384*pi
E 126*pi
F 336*pi
13. volume of the cone
A 158*pi
B 268*pi
C 558*pi
D 255*pi
E 768*pi
F 189*pi
What is surface area and volume of the given shape, if the radius is 9, the height is 12. (Not all shapes will require both numbers.)
14. surface area of the sphere
A 324*pi
B 485*pi
C 312*pi
D 943*pi
E 652*pi
F 645*pi
15. volume of the sphere
A 841*pi
B 126*pi
C 423*pi
D 146*pi
E 479*pi
F 972*pi
16. surface area of the cylinder
A 458*pi
B 145*pi
C 540*pi
D 378*pi
E 405*pi
F 942*pi
17. volume of the cylinder
A 844*pi
B 145*pi
C 548*pi
D 879*pi
E 972*pi
F 655*pi
18. What would the slant height of the cone be?
A 15
B 95
C 24
D 18
E 36
F 27
19. surface area of the cone (with the slant height from # 18)
A 844*pi
B 216*pi
C 469*pi
D 881*pi
E 198*pi
F 112*pi
20. volume of the cone
A 910*pi
B 523*pi
C 128*pi
D 294*pi
E 341*pi
F 324*pi
#42 Re: Help Me ! » Areas Review » 2013-11-03 20:06:33
Yes! They were all correct. Thank you so much again
#43 Re: Help Me ! » Areas Review » 2013-11-03 08:13:32
Alright, thank you very much!
Thank you so much for your help. There's a lesson I'm gonna need help with tomorrow. I'll tell you when i submit the topic.
Thanks again!
#44 Re: Help Me ! » Areas Review » 2013-11-03 07:23:41
An approximate answer is fine, how can I solve it?
#45 Re: Help Me ! » Areas Review » 2013-11-03 07:11:26
Alright, let's move to 10?
#46 Re: Help Me ! » Areas Review » 2013-11-03 07:08:46
And after that could you also help me with number 10:
10. What is the total grazing area the goat can reach?
#47 Re: Help Me ! » Areas Review » 2013-11-03 06:57:21
Okay that answers the area and the shape. But at the beginning of the question they ask by how much do they overlap.?
#48 Re: Help Me ! » Areas Review » 2013-11-03 06:50:48
Okay so the shape is approximately a square. What is its area?
#49 Re: Help Me ! » Areas Review » 2013-11-03 06:29:25
Okay. How about number 9 now?
9. The areas you found in 7 and 8 overlap each other. How much do they overlap? What *approximate* shape do they make? What is that area?
#50 Re: Help Me ! » Areas Review » 2013-11-03 06:23:18
So answer for 8 is (1/4) x 900 x pi = 225 pi as well?