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.

Math 157 
Ms. Sue,
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. 
Math 157 
Lori,
A = pi x r^2
A = 3.14 x 7 x7
A = 153.86
20/153.86 = $0.13 per square inch 
Math 157 
Ms. Sue,
Right! :)

Math 157 
Lori,
Thank you!

Math 157 
Ms. Sue,
You're welcome.