Question 9:
Kaitlyn and Hakim each bought a tube of candy. Both containers cost the same amount. Which container required more plastic to make?
Candy tube A:
d/2 = r
7/2 = r
3.5 cm = r
TSA= (2 x Pi x r x r)+(2 x r x Pi x h)
TSA= (2 x 3.14 x 3.5 x 3.5)+(2 x 3.5 x 3.14 x 122)
TSA= (76.93cm2)+(2681.56cm2)
TSA= 2758cm2
The amount of plastic needed to make tube A is 2758cm2.
Candy tube B:
d/2 = r
11/2 = r
5.5 cm = r
TSA= (2 x Pi x r x r)+(2 x r x Pi x h)
TSA= (2 x 3.14 x 5.5 x 5.5)+(2 x 5.5 x 3.14 x 85)
TSA= (189.97cm2)+(2935.9cm2)
TSA= 3125.87cm2
The amount of plastic needed to make tube B is 3125.87cm2.
The tube of candy that needs more plastic is B.
Question 10:
Paper towel is rolled around a cardboard tube. Calcula
te the outside surface area of the tube.
d =2r
d =2 x 2
d =4cm
c = Pi x d
c = 3.14 x 4
c = 12.56cm
l x w = area of a square
12.56 x 27.5 = area of a square
345.4cm2 = area of a square
The out side surface area of the tube is 345.4cm2.
d/2=r
20/2=r
10cm=r
v=(pir^2)h
v=(3.14x10x10)40
v=314cm^2x40cm
v=12650cm^3
Popcorn lover's
d/2=r
30/2=r
15cm=r
v=(pir^2)h
v=(3.14x15x15)20
v=706.5cm^2x20cm
v=14130cm^3
Here is my math video
If Martha wants to get more popcorn for her money she should by the popcorn lover's container.
Question 2:
d/2=r
10/2=r
5cm=r
v=(pir^2)h
v=(3.14x5x5)40
v=78.5cm^2x40cm
v=3140cm^3
d/2=r
8/2=r
4cm=r
v=(pir^2)h
v=(3.14x4x4)40
v=50.24cm^2x40cm
v=2009.6cm^3
3140cm^3 - 2009.6cm^3=1130.4cm^3
Good job Marysa! I like how your post is easy to read. Your work was clear and easy to understand. Next time, add more color, videos, and links.
ReplyDeleteGreat job Marysa! I like how your post is very organized. The picture that you put really popped out. Next time you might want to include a video and/or link.
ReplyDeleteGood job Marysa! I like how your post is so neat! I really like your picture! Next time you should try to add a video if you can so other classmates in grade eight can understand..Other then that your post was really great!
ReplyDelete