subtraction across zeroes

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39. 13. 19. 10. 403 - 25. 200 - 99. Subtraction Across Zeroes. Hundreds Tens Ones. Let ’ s model 102 minus 38 . Begin by showing 102. 102. - 38. Hundreds Tens Ones. If you have 2 ones , can you take away 8 ones ?. 10 2. - 3 8. - PowerPoint PPT Presentation

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Subtraction Across Zeroes

403 - 25

200- 99

39 1913 10

Hundreds Tens Ones

102- 38

Let’s model 102 minus 38. Begin by showing 102.

Hundreds Tens Ones

102- 38

If you have 2 ones, can you take away 8 ones?

Hundreds Tens Ones

102- 38

How can you get more ones? There are no tens to trade!

Hundreds Tens Ones

102- 38

How many tens are in a hundred?

Hundreds Tens Ones

102- 38

1 Hundred is the same as 10 tens!

Good thinking!

Hundreds Tens Ones

102- 38

Now can you get more ones?

Hundreds Tens Ones

102- 38

How many tens and ones now?

9 12

Hundreds Tens Ones

102- 38

What’s the next step?

9 12

4How many ones are left?

Hundreds Tens Ones

102- 38

What’s the next step?

9 12

4How many tens are left?6

Hundreds Tens Ones

203- 57

Let’s model 203 minus 57. Begin by showing 203.

Hundreds Tens Ones

203- 57

If you have 3 ones, can you take 7 ones away?

Hundreds Tens Ones

203- 57

If 10 tens are in one hundred, how many tens are in two hundreds?

10 tens + 10 tens =

20 tens

Hundreds Tens Ones

203- 57

Can you trade one of the 20 tens for ones? How many tens are left?

20 tens- 1 ten =

19 tens

Hundreds Tens Ones

203- 57

That’s 19 tens left

19 tens

19which is the same as 1 hundred and 9 tens.

Hundreds Tens Ones

203- 57

How many ones do you have now?

1913

Hundreds Tens Ones

203- 57

What is 13 ones minus 7 ones?

1913

6

Hundreds Tens Ones

203- 57

Finish subtracting.1913

641

You’ve Got It!

Subtract Across Zeroes

400- 9

3910

193

Subtract Across Zeroes

502- 14

4912

884

Subtract Across Zeroes

608- 234

5

473

10Slow Down

!

Don’t regroup if you don’t have to!

Subtract Across Zeroes

702- 213

6912

984

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