Question

A stained glass window is going to be installed in a semi-circular opening, which is above a 30 inch wide door. If the stained glass window costs $1.40 per square inch, how much will the window cost? Use 3.14 for
π
π
as necessary.

Answer 1

You will need half of the circle with radius of 15 inches.
Area of semi-circle = (πr^2)/2 = 353.25 x $1.40 = $494.55 

Answer 2

Answer: $494.55

Step-by-step explanation:

Given : A stained glass window is going to be installed in a semi-circular opening, which is above a 30 inch wide door.

Then the diameter of the semi-circular glass = 30 inches

Also, the radius of the glass = $\dfrac{30}{2}=15\text{ inches}$

We know that the area of a semicircle is given by :-

$A=\dfrac{1}{2}(\pi)r^2$

Then , the area of the stained glass window  :-

$A=\dfrac{1}{2}(3.14)(15)^2=353.25\text{ sq. inches}$

The cost of window will be :-

$C=353.25\times1.40=\ 494.55$

Hence, the cost of window = $494.55