Question

Marta is making two different charms for necklace . One charm has a 1 cm diameter and a 3.14 centimeter circumference. A similar charm has a diameter of 4 cm. What is the circumference?

Answer 1

Answer is 12.56cm please see attached photo for formula used and steps used to obtain answer.

Answer 2

the length of a circumference is 2pi*r , you have the diameter 0f 4 cm and it radio is 4 /2 = 2 cm

now l= 2*pi*2= 12,5664 cm,it is the length of the circumference