3rd Grade Multiplication Help for Struggling Students

Help with 3rd Grade Multiplication

There are several different methods for multiplying 2-digit numbers by 1-digit numbers. If you can master more than one, you'll have a deeper understanding of multiplication.

Standard Algorithm

This is the way that most students learn to multiply with multi-digit numbers. Write the larger number on top with the single-digit number directly below its ones place. For example, if you're multiplying 30 by five (30 x 5), you would write the five underneath the zero. Then, draw a horizontal line below the five.

The next step is to multiply the bottom number (five) by the number directly above it (zero), and write the answer (zero) beneath these two numbers under the horizontal line. Last, multiply the bottom number (five) by the number in the tens place (three), and write this answer (15) to the left of the number that's already below the horizontal line (zero). The new number under the horizontal line (150) is the correct answer (30 x 5 = 150).

Expanded Form

Another way to solve multiplication problems with 1- and 2-digit numbers is to use your knowledge of place values and expanded form. This method can be especially helpful if you need to solve a problem in your head.

Imagine that you want to multiply 60 by four (60 x 4). Since 60 has a six in the tens place and a zero in the ones place, this means it's equal to six tens, or 10 x 6. You're multiplying 60 by four, and 60 = 10 x 6, so you can get the correct answer by solving this problem: 10 x 6 x 4.

You know that 6 x 4 = 24, and that any number times ten equals itself with an additional zero added on. For instance, 24 x 10 = 240. Putting this all together, we can say that 60 x 4 = 10 x 6 x 4 = 10 x 24 = 240.

Practice Problems

Complete these practice problems using the standard algorithm. Then check your work using the expanded form method, and verify your answers with the key below.

1. 70 x 2 = ?

2. 20 x 8 = ?

3. 50 x 5 = ?

4. 90 x 3 = ?

5. 40 x 7 = ?

Answer Key

1. 70 x 2 = 140

2. 20 x 8 = 160

3. 50 x 5 = 250

4. 90 x 3 = 270

5. 40 x 7 = 280