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?

Base ten blocks.

Three students found the value of . Their work is shown. Explain how each method works.

  1. Tyler’s drawing

    Tyler's drawing of base ten blocks representing 362 plus 354.

  2. Lin’s method

    Addition. Three-hundred plus sixty plus two, plus three-hundred plus fifty plus four, equals six-hundred plus one-hundred ten plus six.

  3. Han’s method

    Addition. Three-hundred and sixty-two plus three-hundred and fifty four equals six plus one-hundred ten plus six-hundred equals seven-hundred sixteen.

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 .

A
Two base ten diagrams. Top diagram, 1 hundred, 5 tens, 7 ones. Bottom diagram, 4 hundreds, 3 tens, 6 ones.
B
Addition. One-hundred plus fifty plus seven, plus four-hundred plus thirty plus six, equals five-hundred plus eighty plus thirteen.
C
Addition. One-hundred fifty-seven, plus four-hundred thirty-six, equals thirteen plus eighty plus five-hundred, equals five-hundred ninety-three.

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