Lesson 3 Partial Products in Algorithms

    • Let’s find partial products.

Warm-up Which One Doesn’t Belong: Multiplying Large Numbers

Which one doesn’t belong?

  1. Diagram, rectangle partitioned vertically into 4 rectangles.
  2. math expression. 4 times 5 thousand, plus, 4 times three hundred, plus, 4 times 40, plus, 4 times 2
  3. Diagram, rectangle partitioned vertically into 3 rectangles.
  4. Diagram, rectangle partitioned vertically into 4 rectangles.

Activity 1 Partial Products Everywhere

  1. Take turns picking out a set of expressions that are equal to when added together. Use the diagrams if they are helpful.

    Diagram, rectangle partitioned vertically and horizontally into 6 rectangles.
    Diagram, rectangle partitioned vertically and horizontally into 6 rectangles.
    Diagram, rectangle partitioned vertically and horizontally into 6 rectangles.

  2. Explain how you know the sum of your expressions is equal to .

  3. What is the value of ? Explain or show your reasoning.

Activity 2 Record Partial Products

Andre

multiply. two hundred forty five times 35.

Clare

multiply. two hundred forty five times 35.

  1. How are Andre’s and Clare’s strategies the same? How are they different?

  2. Create a list of equations to match the partial products Andre and Clare found.

Practice Problem

Problem 1

Find using partial products.