Plz explain , i want to know how to do

the circumference of a circle is 12.3π in. what is the radius of the circle?
a) 3.9 in
b) 5.75 in
c) 6.15 in
d) 10.1 in

Make sure you know the formula pertaining to the question. 

1. c=2(pi)(r)
2. c=2(pi)(d)

r= radius 
d= diameter
c= sircumference

So we are given that the circumference of a circle is 12.3pi and the radius is unknown. 

So let's plug in the known values 

**we use the formula with the radius, becuase we are looking for the radius. 

c=2(pi)(r)
12.3(pi)=2(pi)(r)

divide each side by pi

12.3=2(r)

divide each side by 2

r=6.15 in. 

The answer would be 27 because assuming that each package has 1 bar of soap and 1 tube of toothpaste, after 27 packages they would run out of toothpaste