good afternoon!
DESCRIPTION
Good Afternoon!. Today our lesson will cover The Rules of Subtraction AND Subtraction of multi-digit numbers. 1.) Round 567 to the nearest hundreds place. 1): 600. 2.) Round 67,423 to the nearest thousands place. 2): 67,000. 3.) Round 4,897 to the nearest tens place. 3): 4,900. - PowerPoint PPT PresentationTRANSCRIPT
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