# Lesson 4

Measurement Error (Part 1)

### Lesson Narrative

This lesson is optional. The activities in this lesson and the next all address the concept of measurement error. Any of these activities can stand on its own, although activities in the next lesson are more challenging, and students would likely benefit from doing the earlier ones first. Note that the first activity in this lesson gives students an opportunity to make measurements and analyze the size of the error. The second activity provides the percent error in the measurement in an addition context. In addition to examining accuracy of measurements carefully (MP6), students will work through examples and look for patterns (MP8) in order to hypothesize, and eventually show, how percent error behaves when measurements with error are added to one another.

As with all lessons in this unit, all related standards have been addressed in prior units. This lesson provides an optional opportunity to go deeper and make connections between domains.

### Learning Goals

Teacher Facing

• Estimate a measurement and determine the largest possible percent error of the estimate.
• Generalize (orally) a process for calculating the maximum percent error of measurements that are added together.

### Student Facing

Let’s check how accurate our measurements are.