 # Addition Algorithms S. Matthews. Partial-Sums Method for Addition Add from left to right and column by column. The sum of each column is recorded on a.

## Presentation on theme: "Addition Algorithms S. Matthews. Partial-Sums Method for Addition Add from left to right and column by column. The sum of each column is recorded on a."— Presentation transcript:

Partial-Sums Method for Addition Add from left to right and column by column. The sum of each column is recorded on a separate line. The value of each digit is determined by its place in the numeral.

Let’s practice the value of digits for Partial-Sums. In the problem 23 + 45, we first add the 2 and 4. However, the 2 is worth 2 tens, and the 4 is worth 4 tens. So we say 20, not 2; and 40, not 4. In the problem 23 + 45, we first add the 2 and 4. However, the 2 is worth 2 tens, and the 4 is worth 4 tens. So we say 20, not 2; and 40, not 4.

Let’s practice the value of digits for Partial-Sums. Your turn. What do we say when adding the hundred’s place for 376 + 832? Your turn. What do we say when adding the hundred’s place for 376 + 832?

You’ve got it! We say 300, not 3; and 800, not 8. What is the sum of the 100’s place? You’ve got it! We say 300, not 3; and 800, not 8. What is the sum of the 100’s place?

Can’t fool you! In 376 and 832, the 3 is worth 300, and the 8 is worth 800. 300 + 800 is 1,100 or eleven hundred. Can’t fool you! In 376 and 832, the 3 is worth 300, and the 8 is worth 800. 300 + 800 is 1,100 or eleven hundred.

Let’s practice the value of digits for Partial-Sums. Let’s continue. What do we say when adding the tens place for 376 + 832? Let’s continue. What do we say when adding the tens place for 376 + 832?

That’s right! We say 70, not 7; and 30, not 3. What is the sum of the 10’s place? That’s right! We say 70, not 7; and 30, not 3. What is the sum of the 10’s place?

Can’t fool you! In 376 and 832, the 7 is worth 70, and the 3 is worth 30. 70 + 30 is 100 or ten tens. Can’t fool you! In 376 and 832, the 7 is worth 70, and the 3 is worth 30. 70 + 30 is 100 or ten tens.

Take a look at the steps for addition using the Partial- Sums Method. Then we’ll practice the method some more. Take a look at the steps for addition using the Partial- Sums Method. Then we’ll practice the method some more.

398 + 435 Add the 100’s: 300 + 400 = + 13 Add the 10’s: 90 + 30 = Add the 1’s: 8 + 5 = Find the total 120 700 833

Now, you try the Partial- sums method using the numbers we practiced.

376 + 832 Add the 100’s: 300 + 800 = + 8 Add the 10’s: 70 + 30 = Add the 1’s: 6 + 2 = Find the total 100 1100 1, 208

You are good! Let’s try just one more. You are good! Let’s try just one more.

479 + 285 Add the 100’s: 400 + 200 = + 14 Add the 10’s: 70 + 80 = Add the 1’s: 9 + 5 = Find the total 150 600 764

Excellent! I know you’ve got the hang of it. Don’t forget, in the Partial-Sums method for addition, you: add the 100’s, add the 10’s, add the 1’s. Then add the sums you just found. (the partial sums) Excellent! I know you’ve got the hang of it. Don’t forget, in the Partial-Sums method for addition, you: add the 100’s, add the 10’s, add the 1’s. Then add the sums you just found. (the partial sums)

Keep practicing. Peace! Keep practicing. Peace!

Download ppt "Addition Algorithms S. Matthews. Partial-Sums Method for Addition Add from left to right and column by column. The sum of each column is recorded on a."

Similar presentations