Using proportions to find the radius of figure 2, we have that:
- The circumference of the base of figure 2 is of [tex]4\pi[/tex] inches.
- The area of the base of figure 2 is of [tex]4\pi[/tex] square inches.
What is a proportion?
A proportion is a fraction of a total amount, and the measures are related using a rule of three. Due to this, relations between variables, either direct or inverse proportional, can be built to find the desired measures in the problem.
The rule of three to find the radius of figure 2 is given as follows:
[tex]\frac{5}{9} = \frac{r}{4.5}[/tex]
Applying cross multiplication:
9r = 4 x 4.5
r = 4 x 4.5/9
r = 2 in
What is the circumference of a circle?
The circumference of a circle of radius r is given by:
[tex]C = 2\pi r[/tex]
In this problem, we have that r = 2 inches, hence:
[tex]C = 2\pi \times 2 = 4\pi[/tex]
What is the area of a circle?
The area of a circle of radius r is given by pi multiplied by the radius squared, as follows:
[tex]A = \pi r^2[/tex]
Hence:
[tex]A = 4\pi[/tex]
More can be learned about proportions at https://brainly.com/question/24372153
#SPJ1
