The circumference of a circle is 19pi ft. What is the area, in square feet? Express your answer in terms of pi.

A = 90.25 pi ft^2

Step-by-step explanation:

The circumference is given by

C = 2 * pi* r

19pi = 2 * pi * r

Divide each side by 2pi

19pi/2pi = 2 * pi *r/2pi

9.5 = r

Now find the area

A = pi r^2

A = pi ( 9.5)^2

A = 90.25 pi ft^2

Step-by-step explanation:

Circumference is found in

while area is

Since we know the circumference value, we can plug it in and solve for r:

Since and , then

and

The pi's cancel out, leaving us with the fact that

We will use that now in the area formula:

so

A = 90.25π

one that is bigger than 3 1/2

d. $180

step-by-step explanation:

if the dimensions of the room is 9ft by 12 ft, we have the area of the floor as,

so the area of the floor is 108 square feet, converting that into square yards we get,

the cost of carpet is $15 per square yard, therefore the cost of carpet for 12 square yards is,

hence, the cost of carpet is $180.

assuming the dimensions of the room be,

15 ft by 12 ft

so, the area of the floor of that room is,

we can convert 180 square feet into square yards, we know that,

1 sq ft = 0.111 sq yard

so, 180 square feet is,

so the area of floor is 20 square yards.

now, the cost of carpet is 15 dollars per square yard, therefore the cost of carpet for 20 square yards is,

so, it will cost $300.