# Lesson 4 Introduction to Addition Algorithms

Let’s learn new ways to add.

## Warm-up Which One Doesn’t Belong: 247

Which one doesn’t belong?

## Activity 1 What is an Algorithm?

Three students found the value of

Tyler’s drawing

Lin’s method

Han’s method

## Activity 2 Try an Algorithm

Try using an algorithm to find the value of each sum. Show your thinking. Organize it so it can be followed by others.

## Practice Problem

## Problem 1

Here are three different ways to find the value of

How are the methods alike? How are they different? Explain your reasoning.