Question

There below! Can somebody help me please?

Answer 1

Answer: C. 24 units

Step-by-step explanation:

The circumference of a circle is 2πr.  Let's say x = 1/3r.  Thus, the area of circle A relative to circle B is 1:3.  Thus, circle B is 3 times larger than circle A.  So, simply divide 64π by 4 to get 16π.  Then multiply 16π*3=48π.  For the circumference of a circle to be 48, the radius would have to be 24.

Hope it helps <3

Answer 2

Answer:

The answer is C, 24 units.

Step-by-step explanation:

Let $r_A$ be the radius is circle A and $r_B$ be the radius of circle B.

Radius of circle A is 1/3 of the radius of circle B, or:

$r_A=\frac{1}{3}r_B$

$3r_A=r_B$

The sum of their circumferences is $64\pi$. In other words:

$2\pi r_A +2\pi r_B = 64\pi$

Substitute $r_B$:

$2\pi(r_A +r_B)=64\pi$

$2\pi (r_A +3r_A)=64\pi$

$4r_A=32, r_A=8$

$r_B=3r_A, r_B=3(8)=24$