The purpose of this activity is to engage students in using ratios to find a common ratio (scale factor).
This activity assumes the students have experience in the following areas:
The problem is sufficiently open ended to allow the students freedom of choice in their approach. It may be scaffolded with guidance that leads to a solution, and/or the students might be given the opportunity to solve the problem independently.
The example responses at the end of the resource give an indication of the kind of response to expect from students who approach the problem in particular ways.
Task: A family sized pizza is baked in a pan that has twice the base area of a standard pizza pan.
Find how much bigger the radius of the family pizza pan is than the standard (ie find the scale factor for this enlargement).
The following prompts illustrate how this activity can be structured around the phases of the Mathematics Investigation Cycle.
Introduce the problem. Allow students time to read it and discuss in pairs or small groups.
Discuss ideas about how to solve the problem. Emphasise that, in the planning phase, you want students to say how they would solve the problem, not to actually solve it.
Allow students time to work through their strategy and find a solution to the problem.
Allow students time to check their answers and then either have them pair share with other groups or ask for volunteers to share their solution with the class.
The student finds a decimal scale factor, using concrete examples in their calculations.
Click on the image to enlarge it. Click again to close.
The student finds an exact (surd) way to record the scale factor, using concrete examples in their calculations.
Click on the image to enlarge it. Click again to close.
The student finds an exact (surd) way to record the scale factor, using algebraic generalisations.
Printed from https://nzmaths.co.nz/resource/pizza-pans at 1:36pm on the 20th April 2024