# Measuring the Size of the Earth from Arizona

## Summary

In this activity, students use the geometric method of Eratosthenes and geographic data from Arizona to estimate the circumference of the earth. The circumference is then used to compute the radius and volume of the Earth.

Click here to view the full activity on the Kéyah Math Project website.

Click here to view the full activity on the Kéyah Math Project website.

## Learning Goals

**Objectives**

**Mathematical Skills**

## Context for Use

This activity consists of a set of quantitative problem-solving exercises that can be used as an in-class activity or an assignment in any introductory geology, geography, or Earth and space sciences course.

## Description and Teaching Materials

## Teaching Notes and Tips

An Instructor's Guide to all Kéyah Math activities is available online from the Instructor Resources page on the Kéyah Math website.

## Assessment

Students record their work and answers in a word-processor document or a notebook, which can be submitted to the instructor for assessment. Solutions to these problems are available online from the Instructor Resources page on the Kéyah Math website.

## References and Resources

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