# Lesson Video: Writing Multiplication Sentences Mathematics • 3rd Grade

In this video, we will learn how to write multiplication sentences matching models.

10:19

### Video Transcript

Writing Multiplication Sentences

In this video, we will learn how to write multiplication sentences to match models.

Let’s think about how to write this model as a multiplication sentence. Here’s a multiplication sentence. We need to think about the missing numbers. Let’s think about what the picture shows. There are three groups, three groups of carrots. How many carrots are there in each group? There are three. There are three groups of carrots, and each group contains three carrots.

We can use our model to help us write our multiplication sentence. The first number is the number of groups we have. We have three groups of carrots. And our second number tells us how many there are in each group. Again, there are three carrots in each group. Three times three or three multiplied by three. What’s the total? What is three multiplied by three? Let’s count in threes to help us find the answer. Three, six, nine. Three multiplied by three is nine.

What multiplication sentence could we write to match this model?

Our first number is the number of groups we have. So, let’s count them. There’s one, two, three, four, five groups. So, we can write our first number in our multiplication sentence, five multiplied by what. The second number is the number of counters in each group. Each group contains two counters. So, our multiplication sentence, so far, is five multiplied by two. Now, what we need to do is work out the total number of counters.

What is five multiplied by two? To work out the answer, we could count in twos five times. Two, four, six, eight, 10. The total number of counters is 10. Five multiplied by two equals 10.

Let’s practice writing some multiplication sentences.

Use the picture to find all the missing numbers. There are what groups. There are what cars in each group. There are four times two equals what cars in total.

This is a three-part question. We have to find all three missing numbers. And we’re told to use the picture to help. In the first part of the question, we have to work out how many groups there are. In other words, how many groups of cars can you see? Let’s count them. Here’s one group, two, three, four. There are four groups of cars.

Next, we need to count the number of cars in each group. Let’s use some counters to help. This group has one, two cars. There are two cars in each group. There are four groups of two cars. So, our multiplication sentence is four times two.

Now, what we need to do is work out the total number of cars. Let’s count in twos. Two, four, six, eight. Four times two is eight. There are four groups. There are two cars in each group. There are four times two equals eight cars in total.

Use the model to find all the missing numbers. What groups of four is 20. Five times what equals 20.

We’re shown a model, which we have to use to find the missing numbers. In the first part of the question, we need to work out how many groups of four make 20. Let’s count how many groups there are. There’s one, two, three, four, five groups. Five groups of four is 20. Did you notice that both of the multiplication sentences now begin with the number five? So, we know the number of groups is five.

Do we know how many counters there are in each group? Yes, we do, five groups of four. And we can count the number of counters in each group to check. Five times four equals 20. One group of four is four, two groups of four are eight, three groups of four are 12, four groups of four are 16, and five groups of four are 20. Five groups of four is 20. Five times four equals 20. The missing numbers are five and four.

Which equation describes the number of dots in this model? 15 divided by three equals five. Three times five equals 15. Five plus three equals 15. Or 15 divided by five equals three.

We have to choose which of these four equations describes the number of dots in the model. How many groups of dots are there? Let’s count. One, two, three. How many dots are there in each group? Did you count? There are five dots in each group. What is three groups of five? To work out how many dots there are in total, we could count in fives. Five, 10, 15. Three groups of five is 15.

Which number sentence says that there are three groups of five dots which equals 15? It can’t be the first sentence. It doesn’t say three groups of five. Let’s look at the second sentence. Three times five equals 15. Three groups of five dots equals 15. This equation describes the number of dots in the model. Five plus three doesn’t equal 15. It equals eight. We know there are 15 dots in this model. And this sentence is a division sentence. We were looking for a multiplication sentence. Three multiplied by five equals 15.

Gummy bears come in packets of 10. Natalie has three packets of gummy bears. Write a number sentence that shows how many gummy bears she has.

Let’s think about the information we already have. We know that gummy bears come in packets of 10. So, we have groups of 10. And we know that Natalie has three packets of gummy bears. Let’s try and write a number sentence which shows this. We need to write a multiplication sentence. This number tells us the number of packets that Natalie has. How many packets of gummy bears does she have? That’s right. There are three. And we already know that there are 10 gummy bears in each packet. Natalie has three groups of 10 gummy bears.

How many gummy bears does she have in total? We could count in 10s to find the answer. Three lots of 10. One group of 10 or one packet of 10 is 10. Two packets of 10 is 20. And three times 10 is 30. 10, 20, 30. We counted in 10s three times. Three times 10 equals 30. The number sentence that shows how many gummy bears Natalie has is three times 10 equals 30.

What have we learned in this video? We’ve learned how to write multiplication sentences to match models.