Two-Digit Fact Families Video

Jose is at his uncle’s farm. He’s fascinated by all of the animal sounds. Just listen, wow! Jose is going to keep track of the animal sounds he hears.

The first sounds Jose hears come from the horse and the cow. The horse neighed 15 times and the cow mooed 12 times. I wonder how many sounds Jose heard all together.

To find the total amount of sounds from the horse and the cow, we can add 15 and 12 together using a place value chart. The dots in the top row represent the number 15, and the dots in the bottom row represent the number 12. Remember to add the ones place value first, and then the tens.

Great job! 15+12=27.

In this equation, 15 and 12 are the parts, and together they make up the whole, 27. We can use a triangle to help us see the parts and whole. The parts go at the bottom of the triangle, and the whole goes at the top. This triangle is called a fact family triangle.

Fact families can show the connection between numbers in an addition sentence. Watch this! 15+12=27 and 12+15=27. See how we flipped the parts? The fact family triangle helped us create a new addition sentence. Let’s use a fact family triangle to find the connections between the numbers of more animal sounds!

The next sounds Jose hears come from the pig and the turkey. The pig oinked 22 times and the turkey gobbled 53 times. Jose wants to know how many oinks and gobbles he heard in total. We can use a place value chart and a fact family triangle to help!

What numbers will go on the bottom of the triangle?

That’s right! 22 and 53 will go on the bottom of the triangle because they are the parts. The top of the number is the sum of the addition sentence, or the whole. What is the sum of 22 and 53?

Very good! 22+53=75.

Can you help Jose use the fact family triangle to create a different addition sentence for the pig and turkey sounds? Let’s see, we know that 22+53=75. Try flipping the addends.

Very good! 53+22=75. Great job! Let’s add more sounds.

The last sounds Jose hears come from a few chickens and the rooster. The chickens clucked 67 times and the rooster crowed 32 times. They are so loud! Let’s help Jose find out how many clucks and crows he heard in total.

Here is an empty fact family triangle. Can you fill it in?

Correct! 67 and 32 are the parts, so they belong at the bottom of the triangle. Now, what number belongs at the top of the triangle?

Good thinking! We need to add 67 and 32 together, starting with the ones place and then the tens place. 67+32=99.

Very good! 99 is the sum of 67 and 32, so it belongs at the top of the triangle! Now it’s up to you to help Jose create addition sentences using this fact family triangle.

Wow! 67+32=99 and 32+67=99. The fact family triangle helped us understand the connection between 32 and 67!

Thank you for helping Jose count the number of animal noises in the barnyard. You used the fact family triangle to show the connections between the numbers in addition sentences. Great job!