The collar

The collar on the dress has the shape of an annulus 6 cm wide. The circumference of the inner circle is 31.4 cm. How much is cm2 of fabric needed to make one collar?

Correct answer:

S =  301.4973 cm2

Step-by-step explanation:

h=6 cm o2=31.4 cm  r2=o2/(2π)=31.4/(2 3.1416)4.9975 cm r1=r2+h=4.9975+610.9975 cm  S1=π r12=3.1416 10.99752379.9575 cm2 S2=π r22=3.1416 4.9975278.4602 cm2  S=S1S2=379.957578.4602=301.4973 cm2



Did you find an error or inaccuracy? Feel free to write us. Thank you!







You need to know the following knowledge to solve this word math problem:


 
We encourage you to watch this tutorial video on this math problem: video1

Related math problems and questions: