Math 157
posted by Lori on .
A 7 inch pizza cost $8 and a 14 inch pizza costs $20. Tommy says the smaller pizza is a better buy because the larger pizza is twice as big and more than twice as expensive. Do you agree with his reasoning? Explain why or why not.

Area of 7 inch pizza:
A = pi * r^2
A = 3.14 * 3.5 * 3.5
A = 38.465 square inches
8/38.465 = $0.21 per square inch
Follow the above procedure to find the area and cost per square inch of the larger pizza. 
A = pi x r^2
A = 3.14 x 7 x7
A = 153.86
20/153.86 = $0.13 per square inch 
Right! :)

Thank you!

You're welcome.