Subtraction and Addition

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Subtraction with Regrouping: 

Subtraction with Regrouping Mrs. Hicks -

1. Look at the ones.: 

1. Look at the ones. Ask: “Can we take 3 away from 2?” 8 2 - 5 3 If we can’t, then we have to regroup.

2. Regroup as needed.: 

2. Regroup as needed. 8 2 - 5 3 1 st : Go next door to the tens and take one away. 7 2 nd : Add the ten to the ones. 1

3. Subtract the ones.: 

3. Subtract the ones. 8 2 - 5 3 7 1 What is 12 – 3? 9

4. Subtract the tens.: 

4. Subtract the tens. 8 2 - 5 3 7 1 9 What is 7 – 5? 2

Now let’s review the steps…: 

Now let’s review the steps… Look at the ones. Ask: Can we subtract? Regroup as needed: 1. Go to the tens and take one away. 2. Add the ten to the ones. Subtract the ones. Subtract the tens.

We can check our subtraction with addition!: 

We can check our subtraction with addition! 8 2 - 5 3 7 1 9 2 2 9 + 5 3 1 st : Move the answer ’29’ to the top of the addition problem. 2 nd : Move the subtracted number ’53’ across to complete the addition problem.

Now we’re ready to add…: 

Now we’re ready to add… 8 2 - 5 3 7 1 9 2 2 9 + 5 3 3rd: Add the tens – 1st: Add the ones: 9 + 3 2 nd : Regroup the ten. 2 1 8 Don’t forget to add the regrouped one!

Let’s see if we are right…: 

Let’s see if we are right… 8 2 - 5 3 7 1 9 2 2 9 + 5 3 2 1 8 Does the answer of the addition problem ’82’ match the top number of the subtraction problem? Yes!! They match! We are right!

Great Job!: 

Great Job! Now it’s your turn to prove you’re the math wizard!