Math 13.2

Math 13.2

Learning Intention

• I am learning to rewrite subtraction problems given in horizontal form as vertical subtraction algorithm and find the difference.

  
  

Success Criteria

• I can rewrite subtraction problems and find the difference.

  
  

Materials

• Virtual place value chart

• paper

• pencil

Vocabulary

Horizontal-right to left

Vertical- up and down

Multiple Choice

DO NOW:

56-28=

• 35

• 28

Turn and Talk: Breakout Room

Mary adds 45 and 25 and gets 710 for an answer. What error did Mary make?

Janet has 54 rocks in her rock garden. She removes 17 rocks.How many rocks does Janet have now?

54-17=? Rewrite the subtraction in the chart. For each number , write the tens in the Tens column. Then write the ones in the ones column.

I do:

Step 1: Subtract the ones. Can you take 7 ones from 4 ones?

Step 2: Regroup 5 tens and 4 ones as

4 tens, 14 ones.

14 ones -7 ones = ?

Step 3: Write the number of ones left in the ones place.

Step 4:Subtract the tens. Write the number of tens left in the tens place. 4 tens- 1 ten = ?

Step 5: Write the difference as tens and ones.

You do:

There are 57 children in Mr. Gabe’s chorus. 28 of the children are in second grade, and the rest are in third grade. How many children are in third grade?

57-28=?

Multiple Choice

Rewrite the subtraction in the chart.

Subtract the ones and be sure to regroup.

Regroup 5 tens 7 ones as?

• 4 tens , 17 ones

• 5 tens 17 ones

Multiple Choice

What is the number of ones left in the ones place?

17 ones - 8 ones = ?

• 9 ones

• 8 ones

Multiple Choice

Subtract the tens. Write the number of tens in the tens place.

4 tens - 2 tens = ?

• 3 tens

• 2 tens

Multiple Choice

Write the difference as tens and ones.

How many children are in third grade?

• 2 tens, 8 ones

  There are 28 students in third grade.

• 2 tens, 9 ones

  There are 29 students in third grade.

Exit Ticket

Solve

Multiple Choice

Exit ticket: Solve

82 - 56 = ?

• 82

• 34