Part 3 - Area of an Annulus (Pruett)

[color=#cc0000]Before you begin, make sure that you are logged into Google and you see the submit button at the end with your name or photo. If not, login to your google account, refresh the page and then begin. You may want to write your answers on paper in case of technical issues.[/color][br][br][b][size=150]Instructions:[/size][/b][br]This applet allows you to explore the area of an annulus. Then answer the 5 questions below. If you get stuck, use the video to help.

Question 1/5

Which of the following formulas will help you to find the area of an annulus?

[math]2\pi r-2\pi R[/math] [math]2\pi R-2\pi r[/math] [math]\pi r^2-\pi R^2[/math] [math]\pi R^2-\pi r^2[/math]

Question 2/5

Which for the following formulas apply to the image above? (Check all that apply)

[math]144\pi-49\pi[/math] [math][/math][math]5\pi[/math] [math]95\times3.14[/math] [math]\pi12^2-\pi7^2[/math]

Question 3/5

Find the area of the annulus above. [color=#ff0000]Use 3.14 as pi and do not round you answer. Do not include units.[/color]

Question 4/5

Which of the following formulas/amounts matches the image above? Solve the problem first, then select all that apply. (There are 3 correct answers)

[math]A=\left(12.75+2.5\right)^2\pi-5^2\pi[/math] [math]A=12.75^2\left(3.14\right)-5^2\left(3.14\right)[/math] [math]A=\pi15.25^2-\pi2.5^2[/math] [math]A=13^2\pi[/math] [math]A=710.62125[/math] [math]A=\left(12.75+2.5\right)^2\pi-2.5^2\pi[/math]

Question 5/5

The 10 inch minute hand on a clock reaches from the center to the edge of the face of the clock. If the clock has a 3 inch circular rim outside of the edge of the clock then what is the area of the rim?[br][br]Use 3.14 as pi and do not round you answer. Do not include units.