You have a 26cm chain and decide to design a bracelet. Find the radius of the bracelet that can be made from this length of chain. (Use Pi = 22/7)

Question

Please help I'm confused!

 

I feel the question is saying:

C = 26cm

D = ?

Circumference equals 2xPi (2 x 22/7)

So Diameter equals C÷Pi which in this case is 26÷22÷7

26÷22/7= 8.27

R = 1/2 D

So 8.27÷2 = 4.14

Therefore the radius comes to 4.14cm

 

I understand this is the same as Linda said (thank you!) but I actually got this question of my youngest brothers maths homework when he asked me to help him and I was completely stumped. He's only in grade eight and none of the other questions were this complex, which is why I'm questioning my working out. I'm just interested to see what the answer is that's all. I'll let you know when he gets his homework back. Thanks!

 

Answer 1

The given 26 cm is the circumference of the bracelet or the circle and pi = 22/7 I also worked it with pi = 3.14 since this was a division problem

 

C = pi times d  Sorry did not find the pi symbol on the special character list

Where C is the Circumference of the circle

Pi is 22/7

d = diameter of the circle

 

Take the formula C = pi x d and divide each side by pi to get the d isolated

so D = C ÷ pi   now I placed the numbers given into the formula and d = 22/7 ÷ 26 cm or d = 3.14 ÷ 26 cm

 

The diameter = 8.27 cm using pi = 22/7 and the diameter = 8.28 cm using pi = 3.14 

The radius is half of the diameter of a circle so now I divide the given diameter by 2

8.27 ÷ 2 = 4.135 cm or 4.14 cm rounded and 8.28 ÷ 2 = 4.14 cm

 

The diameter of the bracelet is 4.14 cm

 

I hope this helped you!

 

Linda C.