Two-Digit Addition With Regrouping Video

Alan and Jen are at the zoo with their mom. They are learning about aquatic animals in the aquarium exhibit. They see manta rays, whale sharks, and blacktip reef sharks.

Its feeding time in the aquarium and Alan and Jen want to know how much food the animals will eat. Let’s help them keep track of how much food is eaten!

The manta rays will eat first. The zookeeper throws in 26 shrimp and then another 15 shrimp.

Wow, they ate those quickly! We can find the total amount of shrimp eaten by adding these numbers together: 26 + 15.

26 and 15 are large numbers, so let’s use a place value chart to help us add. Since the numbers 26 and 15 have ones and tens places, our place value chart needs a ones and tens section. 26 is made up of 2 tens and 6 ones. We can put 6 dots in the ones section and 2 dots in the tens section.

15 is made up of 1 ten and 5 ones. We can put 5 dots in the ones section and 1 dot in the tens section.

What is the next step?

That’s right! We will add all of the dots together, starting in the ones section. 6 dots plus 5 dots equals 11 dots. Now, the tens section. 2 dots plus 1 dot equals 3 dots.

Uh oh. 3 tens and 11 ones? Alan and Jen don’t know what that number is! The largest number in any place value should be 9, so 11 is much too big. Let’s help them by regrouping. 11 ones is made up of 1 ten and 1 one. We can regroup this number by making these ten ones into one ten. There! Let’s try adding the dots together again. 0 dots plus 1 dot equals 1 dot. 2 dots plus 2 dots equals 4 dots.

4 tens and 1 one in expanded form is 40 +1. That equals 41. The manta rays ate 41 shrimp!

Now it’s time for the whale sharks to eat! The zookeeper throws 58 krill into the water. Then she throws in another 37 krill.

The number 58 has 5 tens and 8 ones. Let’s put 8 dots in the ones section and 5 dots in the tens section.

The number 37 has 3 tens and 7 ones. We can put 7 dots in the ones section and 3 dots in the tens section.

Now it’s time to add up the dots! Let’s start with the ones place. 8 dots plus 7 dots equals 15 dots. Wait! 15 is too large of a number to be in the ones place. Let’s fix the problem by regrouping it! The number 15 is made up of 1 ten and 5 ones. Let’s make these 10 ones into one ten. Very good!

Now try adding the dots together again. In the ones place, 0 dots plus 5 dots equals 5 dots. In the tens place, 5 dots plus 4 dots equals 9 dots.

9 tens and 5 ones in expanded form is 90 +5. 90+5=95. The whale sharks ate 95 krill!

It’s finally time for the blacktip reef sharks to eat! The zookeeper throws 33 squid into the water, followed by another 19 squid. Are you ready to find the total amount of squid eaten? Let’s go!

The number 33 is made up of 3 tens and 3 ones. Let’s put 3 dots in the ones section and 3 dots in the tens section.

The number 19 is made up of 1 ten and 9 ones. We can put 9 dots in the ones section and 1 dot in the tens section.

You know what to do! Let’s add up the dots in the ones place. 3 plus 9 equals 12 dots. 12 is larger than 9, so we know we will need to regroup it! How many tens and ones are in the number 12?

That’s right! 12 is made up of 1 ten and 2 ones.

We can combine these 10 ones into one ten and move it over to the tens section. Very good!

Now that we’ve regrouped the ones, can you find the total sum?

Yes! 0+2=2 and 3+2=5.

5 tens and 2 ones in expanded form is 50 +2. 50+2=52. The blacktip reef sharks ate 52 squid!

The aquatic animals in the aquarium exhibit eat so much food! Thank you for helping Alan and Jen add the shrimp, krill, and squid. Your regrouping skills really helped them!