A rectangular piece of materiel with sides 150cm and 100cm is used to make a circular table cloth?

Question

the diameter of the completed cloth must be 0,9m and 5cm is provided for a hem.How muchmaterial is wasted?

Answer 1

hi,

sides of rectangular piece = 150 cm & 100 cm

area of rectangular piece = 150 x 100 = 15,000 cm^2

Now:

diameter of table = 0.9 m = 0.9 x 100 cm = 90 cm

hern = 5 cm but it shall be on both sides = 2 x 5 cm = 10 cm

diameter of the material to be cut for table cloth = 90 + 10 = 100 cm

Area of material cut for table cloth = pi/4 x 100^2 = 7854 cm^2

material wasted = 15,000 - 7854 = 7146 cm^2

hope to answer you well. keep smiling. bye.

Answer 2

Okay, so first you need to know that .9 meters is 90 cm.

and if the diameter is 90 cm, plus 5 on each side including the hem.  so fore the full circle before sewing, the diameter is 100 cm.

you need to find the area of the circle. the equasion for are is radius times radius times pi.

50 x 50 x 3.14 =   7850

thats how much material you will use.

the area of the rectangle is 15000 (150 x 100)

15000 - 7850 = 7150

7150 cm of the cloth will be wasted. :)

Answer 3

understanding the min area req for the table cloth

a total area of 100x100 cmsq will b req

out of it a circle is drawn 0f dia .9  mtrs

thus

(100x50)+(100x100)-pie*45^2

Answer 4

Easy,

First calculate the area of the rectangle L x W in sq-cm.

Next you need to know the area of the circle.

Careful now, you have to stay with the same units. So a .9m circle becomes 90cm.  Add a 5cm hem around the outside, that makes the total diameter 100 cm.

I'm sure you know how to calculate the area of a circle. (Pi r squared, duh)

.  

Subtract the two areas and difference is the wasted amount.

See I told you it was easy, would I lie to you?