What's a better deal - a 12" pizza for 12.50, or a 20" pizza for 17.50? and the amount of square inches per $?

What's a better deal - a 12" pizza for 12.50, or a 20" pizza for 17.50? And what is the amount of square inches on the pizza per dollar for each one?What's a better deal - a 12" pizza for 12.50, or a 20" pizza for 17.50? and the amount of square inches per $?
This is a fun and practical problem; how do we know how many square inches the pizzas have? We can find this out by calculating their areas, and the area of a circle is A=pi*r^2, where r is the radius. The number of inches we are given for each pizza is their diameters, and we need radius. The radius is half the diameter, so we will use r=6 in for pizza one and r=10 in for pizza 2. Now let's find the area of each pizza:



A1=pi*6*6=113.1 square in



A2=pi*10*10=314.2



Notice that I'm rounding off here, because the numbers have infinite decimal places. Now, to find the price per square inch of each pizza, we divide the area of each pizza by its total cost:



p1=113.1 in^2/12.5=9.048 square in per dollar



p2=314.2/17.5=17.95 in square per dollar



Thus, we can say that we get more area (more pizza) per dollar for the money, making the larger pizza a better deal; hope this helps :)
Well, let's find the area of each pizza. A pizza is a circle, right? So the formula for the area of a circle is:

A = (pi)r^2

A = (pi)(12^2)

A = 144pi



A = (pi)(20^2)

A = 400pi



Now to find the area per dollar:

(144pi) / 12.50 = 11.52pi square inches for the 12" pizza

(400pi) / 17.50 = 22.857pi for the 20" pizza



From this, you can see that you get almost twice as much pizza per dollar with the 20" pizza. Hope this helps :-)What's a better deal - a 12" pizza for 12.50, or a 20" pizza for 17.50? and the amount of square inches per $?
the 12" pizza for $12.50 works out to 11 cents per square inch and the 20" for $17.50 works out to 5.5 cents per square inch. So, basically, you're getting twice as much pizza for only $5 more if you go the route of the 20"
The 18 inch pizza is about 254.5 square inches at about 4.9 cents per square inch



The 20 inch pizza is about 314.2 square inches at about 5.57 cents per square inch.



The 18 inch pizza is surprisingly a better deal.
a 12-inch pizza has 113.04 sq. inches which is 11 cents/sq inch



a 20 inch pizza has 314.15 sq inchs which is about 6 cents/sq inch



THIS QUESTION MADE ME EXTREMELY HUNGRY!!



:-)
Always go for a largest avalable pizza