Lesson 11 Subtraction Algorithms (Part 3)
Let’s learn another algorithm to subtract.
Warm-up Notice and Wonder: Digits that Disappear
What do you notice? What do you wonder?
Activity 1 A New Subtraction Algorithm
Andre and Clare found the value of
Andre’s algorithm
Clare’s algorithm
Complete both algorithms to find the difference.
Andre and Clare started their subtraction in different ways. How did their way of starting affect the steps needed to find the difference?
Activity 2 Try Clare’s Algorithm
Clare used an algorithm to find the value of
Try using her algorithm to find the value of each difference.
Practice Problem
Problem 1
Use an algorithm of your choice to find the value of
. Use an algorithm of your choice to find the value of
.