# Pizza Pi

"Papa John’s pizzas come in four sizes: S, M, L & XL. But which is the best deal? We’ll calculate the area of each circle and the cost per square inch to find out."  This web site provides a slide show, lesson plan, and a student handout. Use the area of a circle to extend problem solving in real world math.

### Standards & Objectives

CCSS.Math.Content.7.G.A.1
Solve problems involving scale drawings of geometric figures, including computing actual lengths and areas from a scale drawing and reproducing a...
CCSS.Math.Content.7.RP.A.1
Compute unit rates associated with ratios of fractions, including ratios of lengths, areas and other quantities measured in like or different...
CCSS.Math.Content.7.RP.A.2
Recognize and represent proportional relationships between quantities.
CCSS.Math.Content.7.RP.A.3
Use proportional relationships to solve multistep ratio and percent problems. Examples: simple interest, tax, markups and markdowns, gratuities and...
GLE 0706.2.3
Develop an understanding of and apply proportionality.
GLE 0706.2.4
Use ratios, rates and percents to solve single- and multi-step problems in various contexts.
GLE 0706.3.5
Understand and graph proportional relationships.
GLE 0706.3.6
Conceptualize the meanings of slope using various interpretations, representations, and contexts.
GLE 0706.4.2
Apply proportionality to converting among different units of measurements to solve problems involving rates such as motion at a constant speed.
GLE 0706.4.3
Understand and use scale factor to describe the relationships between length, area, and volume.
GLE 0706.4.4
Understand and use ratios, derived quantities, and indirect measurements.
SPI 0706.1.3
Recognize whether information given in a table, graph, or formula suggests a directly proportional, linear, inversely proportional, or other nonlinear relationship.
SPI 0706.1.4
SPI 0706.2.6
Express the ratio between two quantities as a percent, and a percent as a ratio or fraction.
SPI 0706.2.7
Use ratios and proportions to solve problems.
SPI 0706.3.4
Interpret the slope of a line as a unit rate given the graph of a proportional relationship.
SPI 0706.3.5
Represent proportional relationships with equations, tables and graphs.
SPI 0706.4.3
Apply scale factor to solve problems involving area and volume.
TSS.Math.7.G.A.1
Solve problems involving scale drawings of geometric figures, including computing actual lengths and areas from a scale drawing and reproducing a scale...
TSS.Math.7.RP.A.1
Compute unit rates associated with ratios of fractions, including ratios of lengths, areas, and other quantities measured in like or different units. For...
TSS.Math.7.RP.A.2
Recognize and represent proportional relationships between quantities.
TSS.Math.7.RP.A.3
Use proportional relationships to solve multi-step ratio and percent problems.

Alignment of this item to academic standards is based on recommendations from content creators, resource curators, and visitors to this website. It is the responsibility of each educator to verify that the materials are appropriate for your content area, aligned to current academic standards, and will be beneficial to your specific students.

Learning objectives:

Students will:

• Given the diameters and prices of different pizzas, evaluate several methods of comparing their relative values
• Use the diameter of a pizza to calculate its area
• Calculate price per square inch as a unit rate and use it as a basis of comparison
• Decompose a pizza’s area into “crust” (annulus) and “pizza” (circle) and represent those areas as percents

### Lesson Variations

Blooms taxonomy level:
Applying