Subtracting 2-Digit Numbers with Base Ten Blocks

What is the first step in subtracting two-digit numbers using base ten blocks?

• Building the larger number

• Subtracting tens first

• Building the smaller number

• Trading ones for tens

How many tens are there in the number 82?

• 8

• 6

• 4

• 2

Why do we need to trade one ten rod for ten ones?

• To make counting easier

• To add more tens

• To facilitate subtraction of ones

• To make the number larger

How many ones do we have after trading one ten rod?

• 2

• 10

• 12

• 20

How many ones are subtracted from the total?

• 4

• 6

• 9

• 12

After subtracting the ones, how many ones are left?

• 4

• 1

• 2

• 3

How many tens are subtracted from the remaining tens?

• 4

• 3

• 2

• 5

How many tens are left after subtracting four tens?

• 3

• 1

• 2

• 4

What is the final difference between 82 and 49?

• 23

• 33

• 53

• 43