Lesson 18 Represent Arrays with Expressions

    • Let’s represent situations with arrays and expressions.

Warm-up How Many Do You See: An Array of Shapes

How many do you see? How do you see them?

Array. 5 rows of 4 triangles.

Activity 1 Represent Array Situations

Use objects or drawings to represent each situations with an array.

Write a multiplication expression to represent each situation.

  1. There are 3 rows of chairs. Each row has 5 chairs.

  2. There are 4 rows of cars. Each row has 5 cars in it.

  3. There are 2 rows of eggs. Each row has 6 eggs.

  4. There are 2 teams of students lined up. Each team has 10 students.

Activity 2 Connect Arrays to Expressions

Draw an array for each multiplication expression. Be prepared to share your reasoning.

Practice Problem

Problem 1

There are 4 rows of water bottles in the box. There are 5 bottles in each row.

Draw an array representing the situation. Then, write a multiplication expression representing the number of water bottles.