CONFIDENTIAL 1

Good Afternoon!

Today our lesson will coverThe Rules of Subtraction AND Subtraction of multi-digit

numbers

1.) Round 567 to the nearest hundreds place.

2.) Round 67,423 to the nearest thousands place.

3.) Round 4,897 to the nearest tens place.

1): 600

2): 67,000

3): 4,900

CONFIDENTIAL 2

Let's review what we learned in the last lesson.

There are several properties of addition

COMMUTITATIVE PROPERTY:

ASSOCIATIVE PROPERTY:

IDENTITY PROPERTY:

We can change the order and the sum stays the same.EXAMPLE: 4 + 6 = 10

6 + 4 = 10

We can change the grouping and the sum stays the same.

EXAMPLE: 2 + (3+ 8) = 10 (2 + 3)+ 8= 10

We can add zero and the sum stays the same.EXAMPLE: 7 +0 = 0

CONFIDENTIAL 3

We add numbers together by firstLINING UP THE DIGITS

Then we need to determine if we mustREGROUP

This is how we regroup.

197+ 35

2

1

7+5=12 so we must REGROUP 12

onesas 1 ten and 2

ones

CONFIDENTIAL 4

Now, let's look at 0 in subtraction.

13 - 0 = 13

If we subtract 0 from any number, the difference is that same number.

57 - 57 = 0

If we subtract a number from itself, the difference is 0.

CONFIDENTIAL 5

We need to line up the digits. Often we need to regroup.

Subtraction is similar to addition.

CONFIDENTIAL 6

3,776 - 879 =

First, we must line up the digits.

3,776- 879

Ones Place

Hundreds Place

We look at a problem here.

Thousands Place

Tens Place

CONFIDENTIAL 7

3,476- 879

We begin by subtracting the ones.

6 16

7

*

Now, we can subtract 9 from 16.

In this case, we cannot subtract 9 from 6 so we need to do the following things :

ADD THEM TO REGROUP IT AS TEN ONES and

THE EXISTING SIX ONES.

LOOK AT THE TENS

PLACE AND BORROW A

TEN

CONFIDENTIAL 8

3,476- 879

Next, we move to the tens place.

Once again, we need to regroup a hundred as 10tens

since we cannot subtract 7 from 6.

6 16

7

316

We add our 10tens to the 6tens to get 16 tens.

Now we can subtract 7 from 16.

9

CONFIDENTIAL 9

3,476- 879

Next, we move to the hundreds place.

Once again, we need to regroup a thousand as 10 hundreds since we cannot subtract 8 from 3.

616

7

316

Now we can subtract 8 from 13.

9

213

5

CONFIDENTIAL 10

3,476- 879

Finally, we move to the thousands place.

6 16

7

316

9

213

5

We subtract 0 from 2.

2,(879 has

zero thousands

even though it

is not written there!)

CONFIDENTIAL 11

Remember that subtraction begins with the top number and starts in the ones place.

27 5-

If the problem is written horizontally....

156 - 78

the top number is the number to the left of the subtraction sign.

It's 7 minus 5

CONFIDENTIAL 12

Let's try one together.

345- 68

Remember to begin in the ones place.

Do you need to regroup?

Let's try another one.

4,135- 1,762

277

2,373

CONFIDENTIAL 13

Addition and Subtraction are INVERSE OPERATIONS

We can check our subtraction work by adding from the bottom up.

421- 187 234

234+ 187 421

CONFIDENTIAL 14

Here are some problems for you to try.

6,394- 2,587

4,521 - 976

5,623- 3,652

3,807 3,545

1,971

CONFIDENTIAL 15

1.) Maria and her family are driving to the Grand Canyon for a vacation. The Grand Canyon is 678 miles

from her home. So far, her family has driven 189 miles. How many more miles do they have left to

drive?1): 489

CONFIDENTIAL 16

2.) Steve is playing a video game and needs 100,000 points to win. He currently has earned 36,482 points.

How manymore points does he need?

2): 63,518

CONFIDENTIAL 17

3.) Fill in the boxes.

input output

RULE: Subtract 204

602

619

735 531

398

823

CONFIDENTIAL 18

Problems

1.) 567 - 0 =

2.) 467 - 259 =

CHECK YOUR WORK

1): 567

2): 208

CONFIDENTIAL 19

3.) 56,789 - 56,789 =

4.) 802 - 788 =

CHECK YOUR WORK

3): 00,000

4): 14

CONFIDENTIAL 20

CHECK YOUR WORK

5.) 5,032 - 4,854 =5): 178

CONFIDENTIAL 21

Let's review what we learned today.

Now, let's look at 0 in subtraction.

13 - 0 = 13

If we subtract 0 from any number, the difference is that same number.

CONFIDENTIAL 22

57 - 57 = 0

If we subtract a number from itself, the difference is 0.

And,

We need to line up the digits. Often we need to regroup.

Subtraction is similar to addition.

CONFIDENTIAL 23

Remember that subtraction begins with the top number and starts in the ones place.

27 5-

If the problem is written horizontally....

156 - 78

the top number is the number to the left of the subtraction sign.

It's 7 minus 5

CONFIDENTIAL 24

Congratulations! You worked hard!

Great job today!

See you in the next session