Grade: Grade 2 Subject: Mathematics Unit: Arrays & Introduction to Multiplication SAT: Algebra ACT: Math

Guided Practice with Arrays

Learn

In this lesson, you will practice building arrays and using them to solve multiplication problems. We will work through problems together step by step.

Review: What is an Array?

An array is a way to arrange objects in equal rows and columns. Arrays help us see multiplication as groups of equal amounts.

Steps to Solve Array Problems

  1. Count the rows - How many rows do you see?
  2. Count items in one row - How many objects are in each row?
  3. Write the multiplication - rows x items per row = total
  4. Use repeated addition to check - Add the same number for each row

Example: Cookie Array

  O O O O
  O O O O
  O O O O
            

Step 1: Count rows = 3 rows

Step 2: Count items per row = 4 cookies

Step 3: Write multiplication: 3 x 4 = ?

Step 4: Check with addition: 4 + 4 + 4 = 12

Answer: 3 x 4 = 12 cookies

Worked Examples

Example 1: Stars in Rows

  * * * * *
  * * * * *
            

How many rows? 2 rows

How many stars in each row? 5 stars

Multiplication sentence: 2 x 5 = 10

Check: 5 + 5 = 10

Example 2: Apples in a Basket

  @ @ @
  @ @ @
  @ @ @
  @ @ @
            

How many rows? 4 rows

How many apples in each row? 3 apples

Multiplication sentence: 4 x 3 = 12

Check: 3 + 3 + 3 + 3 = 12

Example 3: Building an Array from Words

"Draw an array with 3 rows and 6 squares in each row."

  [ ] [ ] [ ] [ ] [ ] [ ]
  [ ] [ ] [ ] [ ] [ ] [ ]
  [ ] [ ] [ ] [ ] [ ] [ ]
            

Multiplication sentence: 3 x 6 = 18

Check: 6 + 6 + 6 = 18 squares total

Practice Problems

Try these problems. Write the multiplication sentence and find the total.

Problem 1

  # # # #
  # # # #
  # # # #
            

Rows: ___ Items per row: ___ Multiplication: ___ x ___ = ___

Problem 2

  O O O O O
  O O O O O
  O O O O O
  O O O O O
            

Rows: ___ Items per row: ___ Multiplication: ___ x ___ = ___

Problem 3

Draw an array with 2 rows and 7 items in each row. Then write the multiplication sentence.

Multiplication: ___ x ___ = ___

Problem 4

  * * *
  * * *
  * * *
  * * *
  * * *
            

Rows: ___ Items per row: ___ Multiplication: ___ x ___ = ___

Problem 5

Draw an array with 5 rows and 4 items in each row. Then write the multiplication sentence.

Multiplication: ___ x ___ = ___

Problem 6

  @ @ @ @ @ @
  @ @ @ @ @ @
            

Rows: ___ Items per row: ___ Multiplication: ___ x ___ = ___

Problem 7

Make an array that shows 3 x 5. How many items total?

Total: ___

Problem 8

  [ ] [ ] [ ] [ ]
  [ ] [ ] [ ] [ ]
  [ ] [ ] [ ] [ ]
  [ ] [ ] [ ] [ ]
  [ ] [ ] [ ] [ ]
  [ ] [ ] [ ] [ ]
            

Rows: ___ Items per row: ___ Multiplication: ___ x ___ = ___

Problem 9

Which array shows 4 x 3? Circle the correct one.

A) 4 rows with 3 in each row

B) 3 rows with 4 in each row

C) Both show 4 x 3

Problem 10

Sam says 2 x 8 = 16 and 8 x 2 = 16. Is Sam correct? Draw two arrays to show your answer.

Check Your Understanding

Answer these questions to see what you have learned.

  1. What are the two things you count in an array? (rows and ___)
  2. If an array has 5 rows with 3 items each, what multiplication sentence does it show?
  3. How can you use addition to check your multiplication answer?
  4. True or False: 4 x 2 and 2 x 4 give the same total.
Click to see answers
  1. Rows and items per row (or columns)
  2. 5 x 3 = 15
  3. Add the same number for each row (repeated addition)
  4. True - both equal 8

Next Steps

  • Practice drawing arrays for different multiplication facts
  • Try finding arrays in real life (egg cartons, muffin tins, windows)
  • Move on to the next lesson: Word Problems with Arrays