13. Find the area of a circle with a
circumference of 26 (pi)feet.
16. Find the circumference of a
circle with an area of 289(pi)mm2.
17. Find the circumference of a
circle with an area of 113.1 in 2
18. Find the area of a circle with a
circumference of 131.95 meters.

13. 169π ft²

16. 34π mm

17. 12π in

18. 441π m²

Step-by-step explanation:

Circumference of a circle is calculated as follows:

C = 2π*r

Area of a circle is calculated as follows:

A = π*r²

where r is the radius of the circle

13. circumference of the circle: 26π ft

Then, its radius is:

26π = 2π*r

r = 26π/(2π) = 13 ft

A = π*13² = 169π ft²

16. area of the circle: 289π mm²

Then, its radius is:

289π = π*r²

r = √289

r = 17 mm

C = 2π*17 = 34π mm

17. area of the circle: 113.1 in²

Then, its radius is:

113.1 = π*r²

r = √(113.1/π)

r = 6 in

C = 2π*6 =  12π in

18. circumference of the circle: 131.95 m

Then, its radius is:

131.95 = 2π*r

r = 131.95/(2π)

r = 21 m

A = π*21² = 441π m²

unless you made a typo, the answers are both a and c.

step-by-step explanation:

1.5/3 is .5 whereas 3/9 is .3333333 not proportional

22/33 is .66666 and 4/6 is also .66666 proportional

2/4 is .5 whereas 142/213 is .66666 not proportional

14/7 is 2 and 7/3.5 is also 2 proportional

you could've also checked it by doing this simple division:

if the larger fraction divides with the smaller fraction to equal 1, it is proportional. so let me show you what i mean:

when i divide 22/33 by 4/6 i get 1, so we know it is proportional, and it is the same with 14/7 and 7/3.5. now if i divide 3/9 by 1.5/3 i get .66666 so therefore we know it is not proportional.

there are many ways to do this so i wanted to show you some possible ways.