Head First 2D Geometry

custom sized pies

212 Chapter 5

Pepperoni crust pizza—but at what price?

Mario’s idea is to offer a pepperoni crust on any pizza. He wants to offer

the best possible value to his customers so he’ll only add the minimum

price needed to cover the cost of the extra pepperoni. Sounds simple,

right? But Mario has a problem with the sequence of events in the pizza

process:

Mario will

add 5 cents

per piece of

pepperoni.

The catch is…Mario’s pizzas are custom sized!

If Mario only offered a couple of pizza sizes you could just make

the crust for each size once and then always add the cost of that

amount. But Mario likes to give his customers as much choice as

possible.

I’d like a 14"

Hawaiian, with

pepperoni crust.

That’s 12

dollars and

60 cents.

I let the customer choose the size

they want—any size—8-inch, 23-inch,

whatever. But to give them the right

price I need to know now many pieces of

pepperoni I’ll use on the edge—before I

make the pizza! Is this possible?

The customer rings up with their order.

1

Mario says how much it will be.

2

Mario makes the pizza.

3

you are here 4 213

circles

Scale: 1cm = 2 inches

Hint: A piece of string can be useful

to measure the outside edge of a

circle

Geometry Detective

Mario needs a way to work out how many pieces of pepperoni it will

take to edge a pizza, ba ...