Adding Tens and Ones

Use Models and Strategies to Add Tens and Ones

Unit 10

2-digit numbers have tens and ones.

TENS on the left and ONES on the right.

Multiple Choice

Which of these numbers has 5 tens?

• 5

• 15

• 50

• 105

A place value chart can help think about TENS and ONES.

You can easily draw one.

Multiple Choice

Which number has 3 tens and 7 ones?

• 713

• 317

• 73

• 37

Multiple Choice

Which number has 8 tens and 2 ones?

• 82

• 80

• 28

• 20

When adding numbers, add tens to tens and ones to ones.

If you have 10 ones, you can regroup to make a "ten".

Multiple Choice

What is the first step when adding 36 + 9?

• Add 3 tens + 9 ones.

• Add 6 ones and 9 ones.

• Add 3 tens + 9 tens.

Multiple Select

Which expressions have a sum of 53?

• 50 + 3

• 49 + 4

• 48 + 5

• 47 + 5

• 46 + 6

Multiple Select

Which expressions have a sum of 72?

• 67 + 6

• 7 + 65

• 8 + 64

• 64 + 9

• 63 + 9

If you have more than 10 ones, REGROUP.

Regrouping means to put together or take apart. In this case, we would group 10 unit cubes to make a rod.

Multiple Choice

Which expression could help you solve 16 + 7?

• 10 + 10

• 15 + 6

• 18 + 7

• 3 + 20

Multiple Choice

Which expression could help you solve 55 + 9?

• 55 - 9

• 56 - 10

• 60 + 4

• 50 + 5

Multiple Choice

Which model does NOT show a strategy to solve 37 + 8?

Multiple Select

Select 2 expressions that could be used to solve 54 + 7.

• 54 + 6 + 1

• 50 + 10

• 50 + 11

• 55 + 5

• 52 + 5